diff --git a/docs/exampleAmortisation.fsx b/docs/exampleAmortisation.fsx
index 480b75c..f63d7e2 100644
--- a/docs/exampleAmortisation.fsx
+++ b/docs/exampleAmortisation.fsx
@@ -37,7 +37,8 @@ let scheduleParameters =
         Principal = 1500_00L<Cent>
         PaymentSchedule = RegularSchedule (
             UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 31),
-            PaymentCount = 5
+            PaymentCount = 5,
+            MaxDuration = ValueNone
         )
         FeesAndCharges = {
             Fees = [||]
diff --git a/docs/exampleAprUs.fsx b/docs/exampleAprUs.fsx
index 255c2a8..cf4ae99 100644
--- a/docs/exampleAprUs.fsx
+++ b/docs/exampleAprUs.fsx
@@ -32,7 +32,7 @@ let principal = 5000_00L<Cent>
 
 let transfers =
     Monthly (1, 1978, 2, 10)
-    |> generatePaymentSchedule 24 Direction.Forward
+    |> generatePaymentSchedule 24 ValueNone Direction.Forward
     |> Array.map(fun d -> { TransferType = Payment; TransferDate = d; Amount = 230_00L<Cent> })
 
 let aprMethod = CalculationMethod.UsActuarial 4
diff --git a/docs/examplePaymentSchedule.fsx b/docs/examplePaymentSchedule.fsx
index 01b3254..7c6be36 100644
--- a/docs/examplePaymentSchedule.fsx
+++ b/docs/examplePaymentSchedule.fsx
@@ -37,7 +37,8 @@ let scheduleParameters =
         Principal = 10000_00L<Cent>
         PaymentSchedule = RegularSchedule (
             UnitPeriodConfig = UnitPeriod.Monthly(1, 2024, 3, 7),
-            PaymentCount = 36
+            PaymentCount = 36,
+            MaxDuration = ValueNone
         )
         FeesAndCharges = {
             Fees = [||]
diff --git a/src/Amortisation.fs b/src/Amortisation.fs
index 5ab575b..7f12153 100644
--- a/src/Amortisation.fs
+++ b/src/Amortisation.fs
@@ -550,7 +550,7 @@ module Amortisation =
             | RegularFixedSchedule regularFixedSchedules ->
                 regularFixedSchedules
                 |> Array.map(fun rfs ->
-                    UnitPeriod.generatePaymentSchedule rfs.PaymentCount UnitPeriod.Direction.Forward rfs.UnitPeriodConfig
+                    UnitPeriod.generatePaymentSchedule rfs.PaymentCount ValueNone UnitPeriod.Direction.Forward rfs.UnitPeriodConfig
                     |> Array.map(fun d ->
                         {
                             PaymentDay = OffsetDay.fromDate sp.AsOfDate d
diff --git a/src/Apr.fs b/src/Apr.fs
index 1e0ef73..7d3ef1d 100644
--- a/src/Apr.fs
+++ b/src/Apr.fs
@@ -111,7 +111,7 @@ module Apr =
             let transferDates = transfers |> Array.map _.TransferDate
             let transferCount = transfers |> Array.length
             let unitPeriod = transferDates |> UnitPeriod.detect UnitPeriod.Direction.Reverse (UnitPeriod.Month 1)
-            let schedule = UnitPeriod.generatePaymentSchedule ((transferCount + 1) * multiple) UnitPeriod.Direction.Reverse unitPeriod |> Array.filter(fun d -> d >= termStart)
+            let schedule = UnitPeriod.generatePaymentSchedule ((transferCount + 1) * multiple) ValueNone UnitPeriod.Direction.Reverse unitPeriod |> Array.filter(fun d -> d >= termStart)
             let scheduleCount = schedule |> Array.length
             let lastWholeMonthBackIndex = 0
             let lastWholeUnitPeriodBackIndex = (scheduleCount - 1) % multiple
@@ -139,7 +139,7 @@ module Apr =
             let transferDates = transfers |> Array.map _.TransferDate
             let transferCount = transfers |> Array.length
             let frequency = transferDates |> UnitPeriod.detect UnitPeriod.Direction.Reverse UnitPeriod.SemiMonth
-            let schedule = UnitPeriod.generatePaymentSchedule (transferCount + 2) UnitPeriod.Direction.Reverse frequency |> Array.filter(fun d -> d >= termStart)
+            let schedule = UnitPeriod.generatePaymentSchedule (transferCount + 2) ValueNone UnitPeriod.Direction.Reverse frequency |> Array.filter(fun d -> d >= termStart)
             let scheduleCount = schedule |> Array.length
             let offset = scheduleCount - transferCount
             [| 0 .. (transferCount - 1) |]
diff --git a/src/CustomerPayments.fs b/src/CustomerPayments.fs
index 8a36ef3..9273192 100644
--- a/src/CustomerPayments.fs
+++ b/src/CustomerPayments.fs
@@ -112,7 +112,7 @@ module CustomerPayments =
     [<Struct>]
     type CustomerPaymentSchedule =
         /// a regular schedule based on a unit-period config with a specific number of payments with an auto-calculated amount
-        | RegularSchedule of UnitPeriodConfig: UnitPeriod.Config * PaymentCount: int
+        | RegularSchedule of UnitPeriodConfig: UnitPeriod.Config * PaymentCount: int * MaxDuration: Duration voption
         /// a regular schedule based on one or more unit-period configs each with a specific number of payments of a specified amount
         | RegularFixedSchedule of RegularFixedSchedule array
         /// just a bunch of payments
diff --git a/src/DateDay.fs b/src/DateDay.fs
index cb667dd..48d5e3d 100644
--- a/src/DateDay.fs
+++ b/src/DateDay.fs
@@ -38,6 +38,12 @@ module DateDay =
     /// a duration of a number of days
     [<Measure>] type DurationDay
 
+    [<RequireQualifiedAccess; Struct>]
+    type Duration = {
+        Length: int<DurationDay>
+        FromDate: Date
+    }
+
     /// day of month, bug: specifying 29, 30, or 31 means the dates will track the specific day of the month where
     /// possible, otherwise the day will be the last day of the month; so 31 will track the month end; also note that it is
     /// possible to start with e.g. (2024, 02, 31) and this will yield 2024-02-29 29 2024-03-31 2024-04-30 etc.
diff --git a/src/FSharp.Finance.Personal.fsproj b/src/FSharp.Finance.Personal.fsproj
index c279552..929f86a 100644
--- a/src/FSharp.Finance.Personal.fsproj
+++ b/src/FSharp.Finance.Personal.fsproj
@@ -33,7 +33,7 @@
   <PropertyGroup Condition="'$(Configuration)'=='Release'">
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <PackageId>FSharp.Finance.Personal</PackageId>
-    <Version>0.14.3</Version>
+    <Version>0.15.0</Version>
     <Authors>Simon Treanor</Authors>
     <PackageDescription>F# Personal Finance Library</PackageDescription>
     <RepositoryUrl>https://github.com/simontreanor/FSharp.Finance.Personal</RepositoryUrl>
diff --git a/src/PaymentSchedule.fs b/src/PaymentSchedule.fs
index db11771..6915a61 100644
--- a/src/PaymentSchedule.fs
+++ b/src/PaymentSchedule.fs
@@ -121,10 +121,10 @@ module PaymentSchedule =
                     if startDate > unitPeriodConfigStartDate then
                         [||]
                     else
-                        generatePaymentSchedule rfs.PaymentCount Direction.Forward rfs.UnitPeriodConfig |> Array.map (OffsetDay.fromDate startDate)
+                        generatePaymentSchedule rfs.PaymentCount ValueNone Direction.Forward rfs.UnitPeriodConfig |> Array.map (OffsetDay.fromDate startDate)
             )
             |> Array.concat
-        | RegularSchedule (unitPeriodConfig, paymentCount) ->
+        | RegularSchedule (unitPeriodConfig, paymentCount, maxDuration) ->
             if paymentCount = 0 then
                 [||]
             else
@@ -132,7 +132,7 @@ module PaymentSchedule =
                 if startDate > unitPeriodConfigStartDate then
                     [||]
                 else
-                    generatePaymentSchedule paymentCount Direction.Forward unitPeriodConfig |> Array.map (OffsetDay.fromDate startDate)
+                    generatePaymentSchedule paymentCount maxDuration Direction.Forward unitPeriodConfig |> Array.map (OffsetDay.fromDate startDate)
 
     /// calculates the number of days between two offset days on which interest is chargeable
     let calculate toleranceOption sp =
diff --git a/src/Rescheduling.fs b/src/Rescheduling.fs
index 7ccfea1..8b902c8 100644
--- a/src/Rescheduling.fs
+++ b/src/Rescheduling.fs
@@ -51,7 +51,7 @@ module Rescheduling =
                 | RegularFixedSchedule regularFixedSchedules ->
                     regularFixedSchedules
                     |> Array.map(fun rfs ->
-                        UnitPeriod.generatePaymentSchedule rfs.PaymentCount UnitPeriod.Direction.Forward rfs.UnitPeriodConfig
+                        UnitPeriod.generatePaymentSchedule rfs.PaymentCount ValueNone UnitPeriod.Direction.Forward rfs.UnitPeriodConfig
                         |> Array.map(fun d -> { PaymentDay = OffsetDay.fromDate sp.StartDate d; PaymentDetails = ScheduledPayment (ScheduledPaymentType.Rescheduled rfs.PaymentAmount) })
                     )
                     |> Array.concat
diff --git a/src/UnitPeriod.fs b/src/UnitPeriod.fs
index dfec05b..8bfdafd 100644
--- a/src/UnitPeriod.fs
+++ b/src/UnitPeriod.fs
@@ -196,14 +196,14 @@ module UnitPeriod =
             | invalidConfig -> fix invalidConfig
 
     /// generates a suggested number of payments to constrain the loan within a certain duration
-    let maxPaymentCount (maxLoanLength: int<DurationDay>) (startDate: Date) (config: Config) =
+    let maxPaymentCount (maxDuration: int<DurationDay>) (config: Config) (startDate: Date) =
         let offset y m td = ((TrackingDay.toDate y m td) - startDate).Days |> fun f -> int f * 1<DurationDay>
         match config with
-        | Single d -> maxLoanLength - offset d.Year d.Month d.Day
-        | Daily d -> maxLoanLength - offset d.Year d.Month d.Day
-        | Weekly (multiple, d) when multiple > 0 -> (maxLoanLength - offset d.Year d.Month d.Day) / (multiple * 7)
-        | SemiMonthly (y, m, d1, _) -> (maxLoanLength - offset y m (int d1)) / 15
-        | Monthly (multiple, y, m, d) when multiple > 0 -> (maxLoanLength - offset y m (int d)) / (multiple * 30)
+        | Single d -> maxDuration - offset d.Year d.Month d.Day
+        | Daily d -> maxDuration - offset d.Year d.Month d.Day
+        | Weekly (multiple, d) when multiple > 0 -> (maxDuration - offset d.Year d.Month d.Day) / (multiple * 7)
+        | SemiMonthly (y, m, d1, _) -> (maxDuration - offset y m (int d1)) / 15
+        | Monthly (multiple, y, m, d) when multiple > 0 -> (maxDuration - offset y m (int d)) / (multiple * 30)
         | _ -> 0<DurationDay>
         |> int
 
@@ -216,8 +216,12 @@ module UnitPeriod =
         | Reverse
 
     /// generate a payment schedule based on a unit-period config
-    let generatePaymentSchedule count direction unitPeriodConfig =
+    let generatePaymentSchedule count maxDuration direction unitPeriodConfig =
         if count = 0 then [||] else
+        let limitedCount =
+            match maxDuration with
+            | ValueSome { Duration.Length = d; Duration.FromDate = fd } -> maxPaymentCount d unitPeriodConfig fd
+            | ValueNone -> count
         let adjustMonthEnd (monthEndTrackingDay: int) (d: Date) =
             if d.Day > 15 && monthEndTrackingDay > 28 then
                 TrackingDay.toDate d.Year d.Month monthEndTrackingDay
@@ -237,13 +241,13 @@ module UnitPeriod =
                     startDate.AddMonths c |> adjustMonthEnd monthEndTrackingDay
                     startDate.AddMonths (c + offset) |> fun d -> TrackingDay.toDate d.Year d.Month td2 |> adjustMonthEnd monthEndTrackingDay
                 |])
-                >> Array.take count
+                >> Array.take limitedCount
             | Monthly (multiple, year, month, td) ->
                 let startDate = TrackingDay.toDate year month td
                 Array.map (fun c -> startDate.AddMonths (c * multiple) |> adjustMonthEnd td)
         match direction with
-        | Direction.Forward -> [| 0 .. (count - 1) |] |> generate unitPeriodConfig
-        | Direction.Reverse -> [| 0 .. -1 .. -(count - 1) |] |> generate unitPeriodConfig |> Array.sort
+        | Direction.Forward -> [| 0 .. (limitedCount - 1) |] |> generate unitPeriodConfig
+        | Direction.Reverse -> [| 0 .. -1 .. -(limitedCount - 1) |] |> generate unitPeriodConfig |> Array.sort
 
     /// for a given interval and array of dates, devise the unit-period config
     let detect direction interval (transferDates: Date array) =
diff --git a/tests/ActualPaymentTests.fs b/tests/ActualPaymentTests.fs
index dc6ce7b..7380d2b 100644
--- a/tests/ActualPaymentTests.fs
+++ b/tests/ActualPaymentTests.fs
@@ -67,7 +67,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 31),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -113,7 +114,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 31),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -159,7 +161,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -205,7 +208,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -275,7 +279,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -345,7 +350,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -420,7 +426,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -493,7 +500,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, startDate.AddDays 14),
-                PaymentCount = 11
+                PaymentCount = 11,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -567,7 +575,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -642,7 +651,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -716,7 +726,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -790,7 +801,8 @@ module ActualPaymentTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -866,7 +878,8 @@ module ActualPaymentTests =
             Principal = 250_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2024, 2, 22),
-                PaymentCount = 4
+                PaymentCount = 4,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -914,7 +927,8 @@ module ActualPaymentTests =
             Principal = 2500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(1, Date(2022, 5, 6)),
-                PaymentCount = 24
+                PaymentCount = 24,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 154.47m, ValueNone, ValueSome RoundDown)) |]
@@ -985,7 +999,8 @@ module ActualPaymentTests =
             Principal = 2500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(1, Date(2022, 5, 6)),
-                PaymentCount = 24
+                PaymentCount = 24,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 154.47m, ValueNone, ValueSome RoundDown)) |]
@@ -1033,7 +1048,8 @@ module ActualPaymentTests =
             Principal = 2500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(1, Date(2022, 5, 6)),
-                PaymentCount = 24
+                PaymentCount = 24,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 154.47m, ValueNone, ValueSome RoundDown)) |]
@@ -1082,7 +1098,8 @@ module ActualPaymentTests =
             Principal = 2500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(1, Date(2022, 5, 6)),
-                PaymentCount = 24
+                PaymentCount = 24,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 154.47m, ValueNone, ValueSome RoundDown)) |]
@@ -1132,7 +1149,8 @@ module ActualPaymentTests =
             Principal = 2500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(1, Date(2024, 1, 14)),
-                PaymentCount = 24
+                PaymentCount = 24,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 154.47m, ValueNone, ValueSome RoundDown)) |]
@@ -1182,7 +1200,8 @@ module ActualPaymentTests =
             Principal = 2500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(1, Date(2024, 1, 14)),
-                PaymentCount = 24
+                PaymentCount = 24,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 154.47m, ValueNone, ValueSome RoundDown)) |]
@@ -1230,7 +1249,7 @@ module ActualPaymentTests =
             AsOfDate = Date(2024, 3, 2)
             StartDate = Date(2023, 8, 20)
             Principal = 250_00L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 9, 5), 4)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 9, 5), 4, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
diff --git a/tests/ActualPaymentTestsExtra.fs b/tests/ActualPaymentTestsExtra.fs
index d810718..d8833ac 100644
--- a/tests/ActualPaymentTestsExtra.fs
+++ b/tests/ActualPaymentTestsExtra.fs
@@ -118,7 +118,7 @@ module ActualPaymentTestsExtra =
         let pir = match sp.Interest.PromotionalRates with [||] -> "()" | pirr -> pirr |> Array.map(fun pr -> $"""({pr.DateRange.Start.ToString()}-{pr.DateRange.End.ToString()}__{Interest.Rate.serialise pr.Rate})""") |> String.concat ";" |> fun s -> $"({s})"
         let upc, pc =
             match sp.PaymentSchedule with
-            | RegularSchedule(unitPeriodConfig, paymentCount) ->
+            | RegularSchedule(unitPeriodConfig, paymentCount, maxDuration) ->
                 (UnitPeriod.Config.serialise unitPeriodConfig), paymentCount
             | _ -> failwith "Not implemented"
         let acm = sp.Calculation.AprMethod
@@ -185,7 +185,8 @@ module ActualPaymentTestsExtra =
                 Principal = aa
                 PaymentSchedule = RegularSchedule (
                     UnitPeriodConfig = upc,
-                    PaymentCount = pc
+                    PaymentCount = pc,
+                    MaxDuration = ValueNone
                 )
                 FeesAndCharges = {
                     Fees = f
@@ -236,7 +237,8 @@ module ActualPaymentTestsExtra =
                 Principal = aa
                 PaymentSchedule = RegularSchedule (
                     UnitPeriodConfig = upc,
-                    PaymentCount = pc
+                    PaymentCount = pc,
+                    MaxDuration = ValueNone
                 )
                 FeesAndCharges = {
                     Fees = f
@@ -326,7 +328,8 @@ module ActualPaymentTestsExtra =
             Principal = 800_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2023, 8, 1),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 150m, ValueNone, ValueSome RoundDown)) |]
@@ -401,7 +404,8 @@ module ActualPaymentTestsExtra =
             Principal = 800_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, Date(2022, 3, 26)),
-                PaymentCount = 12
+                PaymentCount = 12,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 150m, ValueNone, ValueSome RoundDown)) |]
@@ -478,7 +482,8 @@ module ActualPaymentTestsExtra =
             Principal = 800_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, Date(2022, 3, 26)),
-                PaymentCount = 12
+                PaymentCount = 12,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 150m, ValueNone, ValueSome RoundDown)) |]
@@ -562,7 +567,8 @@ module ActualPaymentTestsExtra =
             Principal = 800_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly (8, Date(2023, 11, 23)),
-                PaymentCount = 19
+                PaymentCount = 19,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 164m, ValueNone, ValueSome RoundDown)) |]
@@ -637,7 +643,8 @@ module ActualPaymentTestsExtra =
             Principal = 200_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly (1, 2022, 9, 15),
-                PaymentCount = 7
+                PaymentCount = 7,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -712,7 +719,8 @@ module ActualPaymentTestsExtra =
             Principal = 800_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, Date(2022, 3, 26)),
-                PaymentCount = 12
+                PaymentCount = 12,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 150m, ValueNone, ValueSome RoundDown)) |]
@@ -789,7 +797,8 @@ module ActualPaymentTestsExtra =
             Principal = 800_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, Date(2022, 3, 26)),
-                PaymentCount = 12
+                PaymentCount = 12,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 150m, ValueNone, ValueSome RoundDown)) |]
@@ -872,7 +881,8 @@ module ActualPaymentTestsExtra =
             Principal = 800_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, Date(2022, 3, 26)),
-                PaymentCount = 12
+                PaymentCount = 12,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 150m, ValueNone, ValueSome RoundDown)) |]
diff --git a/tests/AprUsActuarialTests.fs b/tests/AprUsActuarialTests.fs
index 0c1e052..8792b4a 100644
--- a/tests/AprUsActuarialTests.fs
+++ b/tests/AprUsActuarialTests.fs
@@ -25,7 +25,7 @@ module AprUsActuarialTests =
         let consummationDate = advanceDate
         let firstFinanceChargeEarnedDate = consummationDate
         let advances = [| { TransferType = Advance; TransferDate = consummationDate; Amount = advanceAmount } |]
-        let payments = intervalSchedule |> UnitPeriod.generatePaymentSchedule paymentCount Direction.Forward |> Array.map(fun d -> { TransferType = Payment; TransferDate = d; Amount = payment })
+        let payments = intervalSchedule |> UnitPeriod.generatePaymentSchedule paymentCount ValueNone Direction.Forward |> Array.map(fun d -> { TransferType = Payment; TransferDate = d; Amount = payment })
         UsActuarial.generalEquation consummationDate firstFinanceChargeEarnedDate advances payments
         |> getAprOr 0m |> Percent.fromDecimal |> Percent.round 2
 
@@ -64,7 +64,7 @@ module AprUsActuarialTests =
         let consummationDate = advanceDate
         let firstFinanceChargeEarnedDate = consummationDate
         let advances = [| { TransferType = Advance; TransferDate = consummationDate; Amount = advanceAmount } |]
-        let payments = intervalSchedule |> generatePaymentSchedule regularPaymentCount Direction.Forward |> Array.map(fun d -> { TransferType = Payment; TransferDate = d; Amount = regularPaymentAmount })
+        let payments = intervalSchedule |> generatePaymentSchedule regularPaymentCount ValueNone Direction.Forward |> Array.map(fun d -> { TransferType = Payment; TransferDate = d; Amount = regularPaymentAmount })
         let payments' = Array.concat [| [| firstPayment |]; payments |]
         UsActuarial.generalEquation consummationDate firstFinanceChargeEarnedDate advances payments'
         |> getAprOr 0m |> Percent.fromDecimal |> Percent.round 2
@@ -88,7 +88,7 @@ module AprUsActuarialTests =
         let consummationDate = advanceDate
         let firstFinanceChargeEarnedDate = consummationDate
         let advances = [| { TransferType = Advance; TransferDate = consummationDate; Amount = advanceAmount } |]
-        let payments = intervalSchedule |> generatePaymentSchedule regularPaymentCount Direction.Forward |> Array.map(fun d -> { TransferType = Payment; TransferDate = d; Amount = regularPaymentAmount })
+        let payments = intervalSchedule |> generatePaymentSchedule regularPaymentCount ValueNone Direction.Forward |> Array.map(fun d -> { TransferType = Payment; TransferDate = d; Amount = regularPaymentAmount })
         let payments' = Array.concat [| payments; [| lastPayment |] |]
         UsActuarial.generalEquation consummationDate firstFinanceChargeEarnedDate advances payments'
         |> getAprOr 0m |> Percent.fromDecimal |> Percent.round 2
@@ -112,7 +112,7 @@ module AprUsActuarialTests =
         let consummationDate = advanceDate
         let firstFinanceChargeEarnedDate = consummationDate
         let advances = [| { TransferType = Advance; TransferDate = consummationDate; Amount = advanceAmount } |]
-        let payments = intervalSchedule |> generatePaymentSchedule regularPaymentCount Direction.Forward |> Array.map(fun d -> { TransferType = Payment; TransferDate = d; Amount = regularPaymentAmount })
+        let payments = intervalSchedule |> generatePaymentSchedule regularPaymentCount ValueNone Direction.Forward |> Array.map(fun d -> { TransferType = Payment; TransferDate = d; Amount = regularPaymentAmount })
         let payments' = Array.concat [| [| firstPayment |]; payments; [| lastPayment |] |]
         UsActuarial.generalEquation consummationDate firstFinanceChargeEarnedDate advances payments'
         |> getAprOr 0m |> Percent.fromDecimal |> Percent.round 2
diff --git a/tests/EdgeCaseTests.fs b/tests/EdgeCaseTests.fs
index f1fe528..119dbf3 100644
--- a/tests/EdgeCaseTests.fs
+++ b/tests/EdgeCaseTests.fs
@@ -425,7 +425,7 @@ module EdgeCaseTests =
             AsOfDate = Date(2024, 3, 12)
             StartDate = Date(2022, 6, 22)
             Principal = 500_00L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2022, 7, 15), 6)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2022, 7, 15), 6, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -545,7 +545,7 @@ module EdgeCaseTests =
             AsOfDate = Date(2024, 3, 12)
             StartDate = Date(2021, 12, 26)
             Principal = 150000L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2022, 1, 7), 6)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2022, 1, 7), 6, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -598,7 +598,7 @@ module EdgeCaseTests =
             AsOfDate = Date(2024, 3, 14)
             StartDate = Date(2024, 2, 2)
             Principal = 25000L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2024, 2, 22), 4)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2024, 2, 22), 4, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -680,7 +680,7 @@ module EdgeCaseTests =
             AsOfDate = Date(2024, 3, 14)
             StartDate = Date(2024, 2, 2)
             Principal = 25000L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2024, 2, 22), 4)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2024, 2, 22), 4, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -762,7 +762,7 @@ module EdgeCaseTests =
             AsOfDate = Date(2024, 4, 5)
             StartDate = Date(2023, 5, 5)
             Principal = 25000L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 5, 10), 4)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 5, 10), 4, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
diff --git a/tests/FeesAndChargesTests.fs b/tests/FeesAndChargesTests.fs
index 6bcfc0f..728ddd9 100644
--- a/tests/FeesAndChargesTests.fs
+++ b/tests/FeesAndChargesTests.fs
@@ -32,7 +32,8 @@ module FeesAndChargesTests =
                 Principal = 1500_00L<Cent>
                 PaymentSchedule = RegularSchedule (
                     UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 31),
-                    PaymentCount = 5
+                    PaymentCount = 5,
+                    MaxDuration = ValueNone
                 )
                 FeesAndCharges = {
                     Fees = [||]
@@ -112,7 +113,8 @@ module FeesAndChargesTests =
                 Principal = 1500_00L<Cent>
                 PaymentSchedule = RegularSchedule (
                     UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 31),
-                    PaymentCount = 5
+                    PaymentCount = 5,
+                    MaxDuration = ValueNone
                 )
                 FeesAndCharges = {
                     Fees = [||]
@@ -192,7 +194,8 @@ module FeesAndChargesTests =
                 Principal = 1500_00L<Cent>
                 PaymentSchedule = RegularSchedule (
                     UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 31),
-                    PaymentCount = 5
+                    PaymentCount = 5,
+                    MaxDuration = ValueNone
                 )
                 FeesAndCharges = {
                     Fees = [||]
diff --git a/tests/InterestTests.fs b/tests/InterestTests.fs
index 3b31b35..e42abd7 100644
--- a/tests/InterestTests.fs
+++ b/tests/InterestTests.fs
@@ -82,7 +82,8 @@ module InterestTests =
                 Principal = 499_00L<Cent>
                 PaymentSchedule = RegularSchedule (
                     UnitPeriodConfig = UnitPeriod.Monthly(1, 2023, 2, 14),
-                    PaymentCount = 4
+                    PaymentCount = 4,
+                    MaxDuration = ValueNone
                 )
                 FeesAndCharges = {
                     Fees = [||]
@@ -127,7 +128,8 @@ module InterestTests =
                 Principal = 499_00L<Cent>
                 PaymentSchedule = RegularSchedule (
                     UnitPeriodConfig = UnitPeriod.Monthly(1, 2023, 2, 14),
-                    PaymentCount = 4
+                    PaymentCount = 4,
+                    MaxDuration = ValueNone
                 )
                 FeesAndCharges = {
                     Fees = [||]
diff --git a/tests/PaymentScheduleTests.fs b/tests/PaymentScheduleTests.fs
index 3a0888f..a5ad5cf 100644
--- a/tests/PaymentScheduleTests.fs
+++ b/tests/PaymentScheduleTests.fs
@@ -32,7 +32,8 @@ module PaymentScheduleTests =
                 Principal = principal
                 PaymentSchedule = RegularSchedule (
                     UnitPeriodConfig = UnitPeriod.Weekly(2, startDate.AddDays(int offset)),
-                    PaymentCount = 11
+                    PaymentCount = 11,
+                    MaxDuration = ValueNone
                 )
                 FeesAndCharges = {
                     Fees = [| Fee.FacilitationFee (Amount.Percentage (Percent 189.47m, ValueNone, ValueSome RoundDown)) |]
@@ -122,7 +123,8 @@ module PaymentScheduleTests =
                 Principal = principal
                 PaymentSchedule = RegularSchedule (
                     UnitPeriodConfig = (startDate.AddDays(int offset) |> fun d -> UnitPeriod.Monthly(1, d.Year, d.Month, d.Day * 1)),
-                    PaymentCount = paymentCount
+                    PaymentCount = paymentCount,
+                    MaxDuration = ValueNone
                 )
                 FeesAndCharges = {
                     Fees = [||]
@@ -1372,7 +1374,8 @@ module PaymentScheduleTests =
             Principal = 300_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Daily(Date(2023, 1, 3)),
-                PaymentCount = 1
+                PaymentCount = 1,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -1407,3 +1410,93 @@ module PaymentScheduleTests =
 
         let expected = ValueSome (336_00L<Cent>, 336_00L<Cent>)
         actual |> should equal expected
+
+    [<Fact>]
+    let ``2) Term must not exceed maximum duration`` () =
+        let sp = {
+            AsOfDate = Date(2024, 5, 8)
+            StartDate = Date(2024, 5, 8)
+            Principal = 1000_00L<Cent>
+            PaymentSchedule = RegularSchedule (
+                UnitPeriodConfig = UnitPeriod.Monthly(1, 2024, 5, 8),
+                PaymentCount = 7,
+                MaxDuration = ValueSome { Length = 183<DurationDay>; FromDate = Date(2024, 5, 8) }
+            )
+            FeesAndCharges = {
+                Fees = [||]
+                FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
+                FeesSettlementRefund = Fees.SettlementRefund.ProRata ValueNone
+                Charges = [| Charge.LatePayment (Amount.Simple 10_00L<Cent>) |]
+                ChargesHolidays = [||]
+                ChargesGrouping = OneChargeTypePerDay
+                LatePaymentGracePeriod = 3<DurationDay>
+            }
+            Interest = {
+                StandardRate = Interest.Rate.Daily (Percent 0.8m)
+                Cap = interestCapExample
+                InitialGracePeriod = 0<DurationDay>
+                PromotionalRates = [||]
+                RateOnNegativeBalance = ValueSome <| Interest.Rate.Annual (Percent 8m)
+            }
+            Calculation = {
+                AprMethod = Apr.CalculationMethod.UnitedKingdom 3
+                RoundingOptions = RoundingOptions.recommended
+                MinimumPayment = DeferOrWriteOff 50L<Cent>
+                PaymentTimeout = 3<DurationDay>
+            }
+        }
+
+        let actual =
+            voption {
+                let! schedule = sp |> calculate BelowZero
+                schedule.Items |> Formatting.outputListToHtml "out/PaymentSchedule002.md"
+                return schedule.LevelPayment, schedule.FinalPayment
+            }
+
+        let expected = ValueSome (269_20L<Cent>, 269_11L<Cent>)
+        actual |> should equal expected
+
+    [<Fact>]
+    let ``3) Term must not exceed maximum duration`` () =
+        let sp = {
+            AsOfDate = Date(2024, 5, 8)
+            StartDate = Date(2024, 5, 8)
+            Principal = 1000_00L<Cent>
+            PaymentSchedule = RegularSchedule (
+                UnitPeriodConfig = UnitPeriod.Monthly(1, 2024, 5, 8),
+                PaymentCount = 7,
+                MaxDuration = ValueSome { Length = 184<DurationDay>; FromDate = Date(2024, 5, 8) }
+            )
+            FeesAndCharges = {
+                Fees = [||]
+                FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
+                FeesSettlementRefund = Fees.SettlementRefund.ProRata ValueNone
+                Charges = [| Charge.LatePayment (Amount.Simple 10_00L<Cent>) |]
+                ChargesHolidays = [||]
+                ChargesGrouping = OneChargeTypePerDay
+                LatePaymentGracePeriod = 3<DurationDay>
+            }
+            Interest = {
+                StandardRate = Interest.Rate.Daily (Percent 0.8m)
+                Cap = interestCapExample
+                InitialGracePeriod = 0<DurationDay>
+                PromotionalRates = [||]
+                RateOnNegativeBalance = ValueSome <| Interest.Rate.Annual (Percent 8m)
+            }
+            Calculation = {
+                AprMethod = Apr.CalculationMethod.UnitedKingdom 3
+                RoundingOptions = RoundingOptions.recommended
+                MinimumPayment = DeferOrWriteOff 50L<Cent>
+                PaymentTimeout = 3<DurationDay>
+            }
+        }
+
+        let actual =
+            voption {
+                let! schedule = sp |> calculate BelowZero
+                schedule.Items |> Formatting.outputListToHtml "out/PaymentSchedule003.md"
+                return schedule.LevelPayment, schedule.FinalPayment
+            }
+
+        let expected = ValueSome (251_08L<Cent>, 250_99L<Cent>)
+        actual |> should equal expected
diff --git a/tests/QuoteTests.fs b/tests/QuoteTests.fs
index 0408575..d4f23fb 100644
--- a/tests/QuoteTests.fs
+++ b/tests/QuoteTests.fs
@@ -34,7 +34,8 @@ module QuoteTests =
             Principal = 1200_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, startDate.AddDays 15),
-                PaymentCount = 11
+                PaymentCount = 11,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 189.47m, ValueNone, ValueSome RoundDown)) |]
@@ -115,7 +116,8 @@ module QuoteTests =
             Principal = 1200_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, startDate.AddDays 15),
-                PaymentCount = 11
+                PaymentCount = 11,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 189.47m, ValueNone, ValueSome RoundDown)) |]
@@ -196,7 +198,8 @@ module QuoteTests =
             Principal = 1200_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, startDate.AddDays 15),
-                PaymentCount = 11
+                PaymentCount = 11,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 189.47m, ValueNone, ValueSome RoundDown)) |]
@@ -277,7 +280,8 @@ module QuoteTests =
             Principal = 1200_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = (startDate.AddDays 15 |> fun sd -> UnitPeriod.Monthly(1, sd.Year, sd.Month, sd.Day * 1)),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -354,7 +358,8 @@ module QuoteTests =
             Principal = 1200_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = (startDate.AddDays 15 |> fun sd -> UnitPeriod.Monthly(1, sd.Year, sd.Month, sd.Day * 1)),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -431,7 +436,8 @@ module QuoteTests =
             Principal = 1200_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, startDate.AddDays 15),
-                PaymentCount = 11
+                PaymentCount = 11,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 189.47m, ValueNone, ValueSome RoundDown)) |]
@@ -512,7 +518,8 @@ module QuoteTests =
             Principal = 1200_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, startDate.AddDays 15),
-                PaymentCount = 11
+                PaymentCount = 11,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 189.47m, ValueNone, ValueSome RoundDown)) |]
@@ -591,7 +598,8 @@ module QuoteTests =
             Principal = 1200_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, startDate.AddDays 15),
-                PaymentCount = 11
+                PaymentCount = 11,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 189.47m, ValueNone, ValueSome RoundDown)) |]
@@ -671,7 +679,8 @@ module QuoteTests =
             Principal = 500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, Date(2023, 6, 30)),
-                PaymentCount = 10
+                PaymentCount = 10,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 150m, ValueNone, ValueSome RoundDown)) |]
@@ -747,7 +756,8 @@ module QuoteTests =
             Principal = 1200_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, Date(2022, 12, 12)),
-                PaymentCount = 11
+                PaymentCount = 11,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 150m, ValueNone, ValueSome RoundDown)) |]
@@ -831,7 +841,8 @@ module QuoteTests =
             Principal = 1200_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Weekly(2, Date(2022, 12, 12)),
-                PaymentCount = 11
+                PaymentCount = 11,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 150m, ValueNone, ValueSome RoundDown)) |]
@@ -913,7 +924,8 @@ module QuoteTests =
             Principal = 400_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2024, 2, 28),
-                PaymentCount = 4
+                PaymentCount = 4,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -988,7 +1000,8 @@ module QuoteTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -1068,7 +1081,8 @@ module QuoteTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -1147,7 +1161,8 @@ module QuoteTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -1226,7 +1241,8 @@ module QuoteTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -1305,7 +1321,8 @@ module QuoteTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -1385,7 +1402,8 @@ module QuoteTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -1465,7 +1483,8 @@ module QuoteTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -1545,7 +1564,8 @@ module QuoteTests =
             Principal = 1500_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2022, 11, 15),
-                PaymentCount = 5
+                PaymentCount = 5,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -1625,7 +1645,8 @@ module QuoteTests =
             Principal = 250_00L<Cent>
             PaymentSchedule = RegularSchedule (
                 UnitPeriodConfig = UnitPeriod.Monthly(1, 2023, 1, 20),
-                PaymentCount = 4
+                PaymentCount = 4,
+                MaxDuration = ValueNone
             )
             FeesAndCharges = {
                 Fees = [||]
@@ -1671,7 +1692,7 @@ module QuoteTests =
             AsOfDate = Date(2024, 3, 4)
             StartDate = Date(2018, 2, 3)
             Principal = 230_00L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2018, 2, 28), 3)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2018, 2, 28), 3, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -1719,7 +1740,7 @@ module QuoteTests =
             AsOfDate = Date(2024, 3, 4)
             StartDate = Date(2018, 2, 3)
             Principal = 230_00L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2018, 2, 28), 3)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2018, 2, 28), 3, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -1767,7 +1788,7 @@ module QuoteTests =
                 AsOfDate = Date(2024, 3, 7)
                 StartDate = Date(2024, 2, 2)
                 Principal = 25000L<Cent>
-                PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2024, 2, 22), 4)
+                PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2024, 2, 22), 4, ValueNone)
                 FeesAndCharges = {
                     Fees = [||]
                     FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -1815,7 +1836,7 @@ module QuoteTests =
                 AsOfDate = Date(2024, 3, 7)
                 StartDate = Date(2023, 9, 2)
                 Principal = 25000L<Cent>
-                PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 9, 22), 4)
+                PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 9, 22), 4, ValueNone)
                 FeesAndCharges = {
                     Fees = [||]
                     FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -1861,7 +1882,7 @@ module QuoteTests =
             AsOfDate = Date(2024, 4, 5)
             StartDate = Date(2023, 5, 5)
             Principal = 25000L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 5, 10), 4)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 5, 10), 4, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
diff --git a/tests/SettlementTests.fs b/tests/SettlementTests.fs
index 5eb9edc..1c247f4 100644
--- a/tests/SettlementTests.fs
+++ b/tests/SettlementTests.fs
@@ -30,7 +30,7 @@ module SettlementTests =
             AsOfDate = Date(2024, 3, 19)
             StartDate = Date(2023, 11, 28)
             Principal = 25000L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 12, 22), 4)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 12, 22), 4, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -106,7 +106,7 @@ module SettlementTests =
             AsOfDate = Date(2024, 3, 29)
             StartDate = Date(2023, 11, 28)
             Principal = 25000L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 12, 22), 4)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 12, 22), 4, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -182,7 +182,7 @@ module SettlementTests =
             AsOfDate = Date(2024, 3, 29)
             StartDate = Date(2023, 11, 28)
             Principal = 25000L<Cent>
-            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 12, 22), 4)
+            PaymentSchedule = RegularSchedule(UnitPeriod.Config.Monthly(1, 2023, 12, 22), 4, ValueNone)
             FeesAndCharges = {
                 Fees = [||]
                 FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
diff --git a/tests/UnitPeriodConfigTests.fs b/tests/UnitPeriodConfigTests.fs
index 7af74b8..167c4a0 100644
--- a/tests/UnitPeriodConfigTests.fs
+++ b/tests/UnitPeriodConfigTests.fs
@@ -64,7 +64,7 @@ module UnitPeriodConfigTests =
                     AsOfDate = Date(2024, 3, 5)
                     StartDate = Date(2022, 5, 5)
                     Principal = 100000L<Cent>
-                    PaymentSchedule = RegularSchedule(Weekly(2, Date(2022, 5, 13)), 12)
+                    PaymentSchedule = RegularSchedule(Weekly(2, Date(2022, 5, 13)), 12, ValueNone)
                     FeesAndCharges = {
                         Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 154.47m, ValueNone, ValueSome RoundDown)) |]
                         FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -140,7 +140,7 @@ module UnitPeriodConfigTests =
                 AsOfDate = Date(2024, 3, 5)
                 StartDate = Date(2023, 4, 13)
                 Principal = 70000L<Cent>
-                PaymentSchedule = RegularSchedule(Weekly(2, Date(2023, 4, 20)), 12)
+                PaymentSchedule = RegularSchedule(Weekly(2, Date(2023, 4, 20)), 12, ValueNone)
                 FeesAndCharges = {
                     Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 154.47m, ValueNone, ValueSome RoundDown)) |]
                     FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -203,7 +203,7 @@ module UnitPeriodConfigTests =
                 AsOfDate = Date(2024, 3, 5)
                 StartDate = Date(2023, 1, 20)
                 Principal = 65000L<Cent>
-                PaymentSchedule = RegularSchedule(Weekly(2, Date(2023, 2, 2)), 11)
+                PaymentSchedule = RegularSchedule(Weekly(2, Date(2023, 2, 2)), 11, ValueNone)
                 FeesAndCharges = {
                     Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 154.47m, ValueNone, ValueSome RoundDown)) |]
                     FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately
@@ -295,7 +295,7 @@ module UnitPeriodConfigTests =
                 AsOfDate = Date(2024, 3, 5)
                 StartDate = Date(2022, 10, 13)
                 Principal = 50000L<Cent>
-                PaymentSchedule = RegularSchedule(Weekly(2, Date(2022, 10, 28)), 11)
+                PaymentSchedule = RegularSchedule(Weekly(2, Date(2022, 10, 28)), 11, ValueNone)
                 FeesAndCharges = {
                     Fees = [| Fee.CabOrCsoFee (Amount.Percentage (Percent 154.47m, ValueNone, ValueSome RoundDown)) |]
                     FeesAmortisation = Fees.FeeAmortisation.AmortiseProportionately