diff --git a/app/controllers/concerns/form_submittable.rb b/app/controllers/concerns/form_submittable.rb
new file mode 100644
index 0000000000..5ea2dbdcb2
--- /dev/null
+++ b/app/controllers/concerns/form_submittable.rb
@@ -0,0 +1,167 @@
+module FormSubmittable
+  extend ActiveSupport::Concern
+
+  #
+  # This concern provides a way of handling form submissions for a generic slug sequence.
+  #
+  # The `new`, `show`, `create`, and `update` actions can be overridden only if necessary,
+  # but it's discouraged as you could easily break the rendering cycle and callback chain.
+  # If you need to override actions, you are probably not dealing with a form-based page sequence.
+  #
+  # The average use case will most likely only require to override slug-specific callbacks
+  # that are used to execute custom logic before, after, or around certain actions.
+  # In some cases, you may not need to define any callbacks at all.
+  #
+  # Default behaviour summary for each action:
+  #
+  #   controller#new: `redirect_to_first_slug`
+  #   controller#show: `before_show` -> `render_template_for_current_slug`
+  #   controller#update: `before_update` -> `handle_form_submission` ->
+  #     -> `form#save` succeded? ->
+  #       -> `execute_callback_if_exists(:after_form_save_success)` OR `redirect_to_next_slug`
+  #     -> `form#save failed?` ->
+  #       -> `execute_callback_if_exists(:after_form_save_failure)` OR `render_template_for_current_slug
+  #   controller#create: same as controller#update
+  #
+  # When including this concern make sure that these methods are accessible in the controller:
+  #
+  # - `slugs`, `current_slug`, `next_slug` (normally from `PageSequence`, or overridden)
+  # - `journey` (from `PartOfJourneyConcern`)
+  # - `current_data_object`, required to load the form object
+  # - any slug-specific callbacks (via a separate mixin)
+  #
+  # Important: `current_slug` is used to generate callbacks and assumed safe to use, i.e. derived
+  # from constrained, validated or sanitised user input.
+  #
+  # Important: If there are other callbacks in the controller, you should be including this concern
+  # **after** all the callbacks are defined. Placing this at the top is most likely a bad idea.
+  # In most cases, form submission callbacks are meant to kick in last.
+  #
+  # See the implementation of `_set_slug_specific_callbacks` below for more details.
+
+  included do
+    before_action :_set_slug_specific_callbacks, only: [:show, :update, :create]
+    before_action :before_show, only: :show
+    before_action :before_update, only: [:update, :create]
+    before_action :load_form_if_exists, only: [:show, :update, :create]
+    around_action :handle_form_submission, only: [:update, :create]
+
+    def current_data_object
+      # This is the instance of the main resource handled by the form object,
+      # and should always be defined in the controller.
+      nil
+    end
+
+    def new
+      redirect_to_first_slug
+    end
+
+    def show
+      render_template_for_current_slug
+    end
+
+    def create
+      # Note: if implemented, this action will be yielded at the end of `handle_form_submission`
+    end
+
+    def update
+      # Note: if implemented, this action will be yielded at the end of `handle_form_submission`
+    end
+
+    private
+
+    #
+    # Slug-specific callbacks are generated and executed around `show`, `update`, `create` actions,
+    # For example, for the "personal-details" slug, the following callbacks are available:
+    #
+    # `personal_details_before_show`
+    # `personal_details_before_update`
+    # `personal_details_after_form_save_success` (*)
+    # `personal_details_after_form_save_failure` (*)
+    #
+    # Ensure that the callbacks are implemented only where really needed.
+    # Consider organizing the callback methods in one mixin per journey and controller.
+    #
+    # (*) If you need to define these callbacks, the default rendering behaviour will not be
+    # followed, so you'll have to explicitly define what to do next (render/redirect_to).
+
+    def _set_slug_specific_callbacks
+      %i[before_show before_update after_form_save_success after_form_save_failure].each do |callback_name|
+        self.class.send(:define_method, callback_name) do
+          execute_callback_if_exists(callback_name)
+        end
+      end
+    end
+
+    def redirect_to_slug(slug)
+      raise NoMethodError, "End of sequence: you must define #{current_slug.underscore}_after_form_save_success" unless next_slug
+      raise NoMethodError, "Missing path helper for resource: \"#{path_helper_resource}\"; try overriding it with #path_helper_resource" unless respond_to?(:"#{path_helper_resource}_path")
+
+      redirect_to send(:"#{path_helper_resource}_path", current_journey_routing_name, slug)
+    end
+
+    def redirect_to_next_slug
+      redirect_to_slug(next_slug)
+    end
+
+    def redirect_to_first_slug
+      redirect_to_slug(first_slug)
+    end
+
+    def path_helper_resource
+      controller_name.singularize
+    end
+
+    def render_template_for_current_slug
+      render current_template
+    end
+
+    def current_template
+      current_slug.underscore
+    end
+
+    def slugs
+      journey.slug_sequence::SLUGS
+    end
+
+    def first_slug
+      slugs.first.to_sym
+    end
+
+    def execute_callback_if_exists(callback_name)
+      callback_name = :"#{current_slug.underscore}_#{callback_name}"
+      if respond_to?(callback_name)
+        log_event(callback_name) { send(callback_name) }
+        return true
+      end
+      false
+    end
+
+    def handle_form_submission
+      log_event(__method__)
+
+      if @form.present?
+        if @form.save
+          return if execute_callback_if_exists(:after_form_save_success)
+          redirect_to_next_slug
+        else
+          return if execute_callback_if_exists(:after_form_save_failure)
+          render_template_for_current_slug
+        end
+      else
+        redirect_to_next_slug
+      end
+
+      yield
+    end
+
+    def log_event(callback_name)
+      logger.info "Executing callback ##{callback_name}"
+      yield if block_given?
+    end
+
+    def load_form_if_exists
+      @form ||= journey.form(claim: current_data_object, journey_session:, params:)
+    end
+  end
+end
diff --git a/app/controllers/journeys/additional_payments_for_teaching/reminders_controller.rb b/app/controllers/journeys/additional_payments_for_teaching/reminders_controller.rb
index ffc8761722..94ce376e3c 100644
--- a/app/controllers/journeys/additional_payments_for_teaching/reminders_controller.rb
+++ b/app/controllers/journeys/additional_payments_for_teaching/reminders_controller.rb
@@ -1,59 +1,21 @@
 module Journeys
   module AdditionalPaymentsForTeaching
     class RemindersController < BasePublicController
-      helper_method :current_reminder
-      after_action :reminder_set_email, :clear_sessions, only: [:show]
-
-      def new
-        # Skip the OTP process if the current_claim already has email_verified
-        # - transfer the email_verified state to the reminder (done in #current_reminder)
-        # - jump straight to reminder set
-        if current_reminder.email_verified? && current_reminder.save
-          redirect_to reminder_path(current_journey_routing_name, "set")
-          return
-        end
+      include PartOfClaimJourney
 
-        render "reminders/#{first_template_in_sequence}"
-      end
-
-      def create
-        current_reminder.attributes = reminder_params
-
-        begin
-          one_time_password
-        rescue Notifications::Client::BadRequestError => e
-          if notify_email_error?(e.message)
-            render "reminders/#{first_template_in_sequence}"
-            return
-          else
-            raise
-          end
-        end
+      after_action :clear_sessions, only: :show
+      helper_method :current_reminder
 
-        if current_reminder.save(context: current_slug.to_sym)
-          session[:reminder_id] = current_reminder.to_param
-          redirect_to reminder_path(current_journey_routing_name, next_slug)
-        else
-          render "reminders/#{first_template_in_sequence}"
-        end
-      end
+      include FormSubmittable
+      include RemindersFormCallbacks
 
-      def show
-        render "reminders/#{current_template}"
-      end
+      private
 
-      def update
-        current_reminder.attributes = reminder_params
-        one_time_password
-        if current_reminder.save(context: current_slug.to_sym)
-          redirect_to reminder_path(current_journey_routing_name, next_slug)
-        else
-          show
-        end
+      # Wrapping `current_reminder` with an abstract method that is fed to the form object.
+      def current_data_object
+        current_reminder
       end
 
-      private
-
       def claim_from_session
         return unless session.key?(:claim_id) || session.key?(:submitted_claim_id)
 
@@ -69,18 +31,6 @@ def slugs
         journey.slug_sequence::REMINDER_SLUGS
       end
 
-      def first_template_in_sequence
-        slugs.first.underscore
-      end
-
-      def current_template
-        current_slug.underscore
-      end
-
-      def next_template
-        next_slug.underscore
-      end
-
       def next_slug
         slugs[current_slug_index + 1]
       end
@@ -93,6 +43,10 @@ def current_slug_index
         slugs.index(params[:slug]) || 0
       end
 
+      def current_template
+        "reminders/#{current_slug.underscore}"
+      end
+
       def current_reminder
         @current_reminder ||=
           reminder_from_session ||
@@ -127,51 +81,12 @@ def next_academic_year
         journey_configuration.current_academic_year + 1
       end
 
-      def reminder_params
-        params.require(:reminder).permit(:full_name, :email_address, :one_time_password)
-      end
-
-      def one_time_password
-        case current_slug
-        when "personal-details"
-          if current_reminder.valid?(:"personal-details")
-            ReminderMailer.email_verification(current_reminder, otp.code).deliver_now
-            session[:sent_one_time_password_at] = Time.now
-          end
-        when "email-verification"
-          current_reminder.update(sent_one_time_password_at: session[:sent_one_time_password_at])
-        end
-      end
-
-      def otp
-        @otp ||= OneTimePassword::Generator.new
-      end
-
-      def reminder_set_email
-        return unless current_slug == "set" && current_reminder.email_verified?
-
-        ReminderMailer.reminder_set(current_reminder).deliver_now
-      end
-
       def clear_sessions
-        return unless current_template == "set"
+        return unless current_slug == "set"
 
         session.delete(:claim_id)
         session.delete(:reminder_id)
       end
-
-      def notify_email_error?(msg)
-        case msg
-        when "ValidationError: email_address is a required property"
-          current_reminder.add_invalid_email_error("Enter an email address in the correct format, like name@example.com")
-          true
-        when "BadRequestError: Can’t send to this recipient using a team-only API key"
-          current_reminder.add_invalid_email_error("Only authorised email addresses can be used when using a team-only API key")
-          true
-        else
-          false
-        end
-      end
     end
   end
 end
diff --git a/app/controllers/journeys/additional_payments_for_teaching/reminders_form_callbacks.rb b/app/controllers/journeys/additional_payments_for_teaching/reminders_form_callbacks.rb
new file mode 100644
index 0000000000..415a32f1dd
--- /dev/null
+++ b/app/controllers/journeys/additional_payments_for_teaching/reminders_form_callbacks.rb
@@ -0,0 +1,83 @@
+module Journeys
+  module AdditionalPaymentsForTeaching
+    module RemindersFormCallbacks
+      def personal_details_before_show
+        try_mailer { set_a_reminder_immediately_if_possible }
+      end
+
+      def email_verification_before_show
+        try_mailer { set_a_reminder_immediately_if_possible }
+      end
+
+      def email_verification_before_update
+        inject_sent_one_time_password_at_into_the_form
+      end
+
+      def personal_details_after_form_save_success
+        update_reminder_id
+        try_mailer { send_verification_email } || return
+        redirect_to_next_slug
+      end
+
+      def email_verification_after_form_save_success
+        try_mailer { send_reminder_set_email } || return
+        redirect_to_next_slug
+      end
+
+      private
+
+      def set_a_reminder_immediately_if_possible
+        return if current_reminder.persisted?
+
+        if current_reminder.email_verified? && current_reminder.save
+          ReminderMailer.reminder_set(current_reminder).deliver_now
+
+          redirect_to reminder_path(current_journey_routing_name, "set")
+        end
+      end
+
+      def inject_sent_one_time_password_at_into_the_form
+        params[:form]&.[]=(:sent_one_time_password_at, session[:sent_one_time_password_at])
+      end
+
+      def update_reminder_id
+        session[:reminder_id] = current_reminder.to_param
+      end
+
+      def send_verification_email
+        otp = OneTimePassword::Generator.new
+        ReminderMailer.email_verification(current_reminder, otp.code).deliver_now
+        session[:sent_one_time_password_at] = Time.now
+      end
+
+      def send_reminder_set_email
+        ReminderMailer.reminder_set(current_reminder).deliver_now
+      end
+
+      def try_mailer(&block)
+        yield if block
+        true
+      rescue Notifications::Client::BadRequestError => e
+        if notify_email_error?(e.message)
+          render_template_for_current_slug
+          false
+        else
+          raise
+        end
+      end
+
+      def notify_email_error?(msg)
+        case msg
+        when "ValidationError: email_address is a required property"
+          @form.errors.add(:email_address, :invalid, message: @form.i18n_errors_path(:"email_address.invalid"))
+          true
+        when "BadRequestError: Can’t send to this recipient using a team-only API key"
+          @form.errors.add(:email_address, :invalid, message: @form.i18n_errors_path(:"email_address.unauthorised"))
+          true
+        else
+          false
+        end
+      end
+    end
+  end
+end
diff --git a/app/forms/email_verification_form.rb b/app/forms/email_verification_form.rb
index 0b6f80b422..c19cee1bc1 100644
--- a/app/forms/email_verification_form.rb
+++ b/app/forms/email_verification_form.rb
@@ -4,7 +4,8 @@ class EmailVerificationForm < Form
   # Required for shared partial in the view
   delegate :email_address, to: :claim
 
-  validate :otp_validate
+  validate :sent_one_time_password_must_be_valid
+  validate :otp_must_be_valid, if: :sent_one_time_password_at?
 
   before_validation do
     self.one_time_password = one_time_password.gsub(/\D/, "")
@@ -18,12 +19,28 @@ def save
 
   private
 
-  def otp_validate
+  def sent_one_time_password_at
+    claim.sent_one_time_password_at
+  end
+
+  def sent_one_time_password_must_be_valid
+    return if sent_one_time_password_at?
+
+    errors.add(:one_time_password, i18n_errors_path(:"one_time_password.invalid"))
+  end
+
+  def otp_must_be_valid
     otp = OneTimePassword::Validator.new(
       one_time_password,
-      claim.sent_one_time_password_at
+      sent_one_time_password_at
     )
 
     errors.add(:one_time_password, otp.warning) unless otp.valid?
   end
+
+  def sent_one_time_password_at?
+    sent_one_time_password_at&.to_datetime || false
+  rescue Date::Error
+    false
+  end
 end
diff --git a/app/forms/form.rb b/app/forms/form.rb
index 4ec6fa113f..77980e241f 100644
--- a/app/forms/form.rb
+++ b/app/forms/form.rb
@@ -9,8 +9,6 @@ class Form
   attr_accessor :journey_session
   attr_accessor :params
 
-  delegate :persisted?, to: :claim
-
   def self.model_name
     Claim.model_name
   end
@@ -53,7 +51,11 @@ def i18n_errors_path(msg, args = {})
   end
 
   def permitted_params
-    @permitted_params ||= params.fetch(:claim, {}).permit(*permitted_attributes)
+    @permitted_params ||= params.fetch(model_name.param_key, {}).permit(*permitted_attributes)
+  end
+
+  def persisted?
+    true
   end
 
   private
diff --git a/app/forms/journeys/additional_payments_for_teaching/reminders/email_verification_form.rb b/app/forms/journeys/additional_payments_for_teaching/reminders/email_verification_form.rb
new file mode 100644
index 0000000000..4547022507
--- /dev/null
+++ b/app/forms/journeys/additional_payments_for_teaching/reminders/email_verification_form.rb
@@ -0,0 +1,13 @@
+module Journeys
+  module AdditionalPaymentsForTeaching
+    module Reminders
+      class EmailVerificationForm < ::EmailVerificationForm
+        attribute :sent_one_time_password_at
+
+        def self.model_name
+          ActiveModel::Name.new(Form)
+        end
+      end
+    end
+  end
+end
diff --git a/app/forms/journeys/additional_payments_for_teaching/reminders/personal_details_form.rb b/app/forms/journeys/additional_payments_for_teaching/reminders/personal_details_form.rb
new file mode 100644
index 0000000000..c993759f91
--- /dev/null
+++ b/app/forms/journeys/additional_payments_for_teaching/reminders/personal_details_form.rb
@@ -0,0 +1,33 @@
+module Journeys
+  module AdditionalPaymentsForTeaching
+    module Reminders
+      class PersonalDetailsForm < Form
+        attribute :full_name
+        attribute :email_address
+
+        validates :full_name, presence: {message: i18n_error_message(:"full_name.blank")}
+        validates :full_name, length: {maximum: 100, message: i18n_error_message(:"full_name.length")}
+
+        validates :email_address, presence: {message: i18n_error_message(:"email_address.blank")}
+        validates :email_address, format: {with: Rails.application.config.email_regexp, message: i18n_error_message(:"email_address.invalid")},
+          length: {maximum: 256, message: i18n_error_message(:"email_address.length")}, if: -> { email_address.present? }
+
+        def self.model_name
+          ActiveModel::Name.new(Form)
+        end
+
+        def save
+          return false unless valid?
+
+          update!(attributes)
+        end
+
+        private
+
+        def i18n_form_namespace
+          "reminders.#{super}"
+        end
+      end
+    end
+  end
+end
diff --git a/app/models/journeys/additional_payments_for_teaching.rb b/app/models/journeys/additional_payments_for_teaching.rb
index 4c007a293c..6f71d4ecad 100644
--- a/app/models/journeys/additional_payments_for_teaching.rb
+++ b/app/models/journeys/additional_payments_for_teaching.rb
@@ -10,23 +10,29 @@ module AdditionalPaymentsForTeaching
     I18N_NAMESPACE = "additional_payments"
     POLICIES = [Policies::EarlyCareerPayments, Policies::LevellingUpPremiumPayments]
     FORMS = {
-      "induction-completed" => InductionCompletedForm,
-      "itt-year" => IttAcademicYearForm,
-      "nqt-in-academic-year-after-itt" => NqtInAcademicYearAfterIttForm,
-      "eligible-degree-subject" => EligibleDegreeSubjectForm,
-      "supply-teacher" => SupplyTeacherForm,
-      "poor-performance" => PoorPerformanceForm,
-      "entire-term-contract" => EntireTermContractForm,
-      "employed-directly" => EmployedDirectlyForm,
-      "qualification" => QualificationForm,
-      "qualification-details" => QualificationDetailsForm,
-      "eligible-itt-subject" => EligibleIttSubjectForm,
-      "teaching-subject-now" => TeachingSubjectNowForm,
-      "eligibility-confirmed" => EligibilityConfirmedForm,
-      "correct-school" => CorrectSchoolForm,
-      "reset-claim" => ResetClaimForm,
-      "postcode-search" => PostcodeSearchForm,
-      "select-home-address" => SelectHomeAddressForm
+      "claims" => {
+        "induction-completed" => InductionCompletedForm,
+        "itt-year" => IttAcademicYearForm,
+        "nqt-in-academic-year-after-itt" => NqtInAcademicYearAfterIttForm,
+        "eligible-degree-subject" => EligibleDegreeSubjectForm,
+        "supply-teacher" => SupplyTeacherForm,
+        "poor-performance" => PoorPerformanceForm,
+        "entire-term-contract" => EntireTermContractForm,
+        "employed-directly" => EmployedDirectlyForm,
+        "qualification" => QualificationForm,
+        "qualification-details" => QualificationDetailsForm,
+        "eligible-itt-subject" => EligibleIttSubjectForm,
+        "teaching-subject-now" => TeachingSubjectNowForm,
+        "eligibility-confirmed" => EligibilityConfirmedForm,
+        "correct-school" => CorrectSchoolForm,
+        "reset-claim" => ResetClaimForm,
+        "postcode-search" => PostcodeSearchForm,
+        "select-home-address" => SelectHomeAddressForm
+      },
+      "reminders" => {
+        "personal-details" => Reminders::PersonalDetailsForm,
+        "email-verification" => Reminders::EmailVerificationForm
+      }
     }.freeze
   end
 end
diff --git a/app/models/journeys/base.rb b/app/models/journeys/base.rb
index 85ca0ae71a..421894d4c7 100644
--- a/app/models/journeys/base.rb
+++ b/app/models/journeys/base.rb
@@ -1,24 +1,26 @@
 module Journeys
   module Base
     SHARED_FORMS = {
-      "sign-in-or-continue" => SignInOrContinueForm,
-      "current-school" => CurrentSchoolForm,
-      "gender" => GenderForm,
-      "personal-details" => PersonalDetailsForm,
-      "select-email" => SelectEmailForm,
-      "provide-mobile-number" => ProvideMobileNumberForm,
-      "select-mobile" => SelectMobileForm,
-      "email-address" => EmailAddressForm,
-      "email-verification" => EmailVerificationForm,
-      "mobile-number" => MobileNumberForm,
-      "mobile-verification" => MobileVerificationForm,
-      "bank-or-building-society" => BankOrBuildingSocietyForm,
-      "personal-bank-account" => BankDetailsForm,
-      "building-society-account" => BankDetailsForm,
-      "teacher-reference-number" => TeacherReferenceNumberForm,
-      "address" => AddressForm,
-      "select-home-address" => SelectHomeAddressForm
-    }
+      "claims" => {
+        "sign-in-or-continue" => SignInOrContinueForm,
+        "current-school" => CurrentSchoolForm,
+        "gender" => GenderForm,
+        "personal-details" => PersonalDetailsForm,
+        "select-email" => SelectEmailForm,
+        "provide-mobile-number" => ProvideMobileNumberForm,
+        "select-mobile" => SelectMobileForm,
+        "email-address" => EmailAddressForm,
+        "email-verification" => EmailVerificationForm,
+        "mobile-number" => MobileNumberForm,
+        "mobile-verification" => MobileVerificationForm,
+        "bank-or-building-society" => BankOrBuildingSocietyForm,
+        "personal-bank-account" => BankDetailsForm,
+        "building-society-account" => BankDetailsForm,
+        "teacher-reference-number" => TeacherReferenceNumberForm,
+        "address" => AddressForm,
+        "select-home-address" => SelectHomeAddressForm
+      }
+    }.freeze
 
     def configuration
       Configuration.find(self::ROUTING_NAME)
@@ -33,7 +35,7 @@ def slug_sequence
     end
 
     def form(claim:, journey_session:, params:)
-      form = SHARED_FORMS.merge(forms)[params[:slug]]
+      form = SHARED_FORMS.deep_merge(forms).dig(params[:controller].split("/").last, params[:slug])
 
       form&.new(journey: self, journey_session:, claim:, params:)
     end
diff --git a/app/models/journeys/teacher_student_loan_reimbursement.rb b/app/models/journeys/teacher_student_loan_reimbursement.rb
index 5240e94500..cf683369d0 100644
--- a/app/models/journeys/teacher_student_loan_reimbursement.rb
+++ b/app/models/journeys/teacher_student_loan_reimbursement.rb
@@ -11,17 +11,19 @@ module TeacherStudentLoanReimbursement
     POLICIES = [Policies::StudentLoans]
 
     FORMS = {
-      "claim-school" => ClaimSchoolForm,
-      "qualification-details" => QualificationDetailsForm,
-      "qts-year" => QtsYearForm,
-      "subjects-taught" => SubjectsTaughtForm,
-      "still-teaching" => StillTeachingForm,
-      "leadership-position" => LeadershipPositionForm,
-      "mostly-performed-leadership-duties" => MostlyPerformedLeadershipDutiesForm,
-      "reset-claim" => ResetClaimForm,
-      "postcode-search" => PostcodeSearchForm,
-      "select-claim-school" => SelectClaimSchoolForm,
-      "select-home-address" => SelectHomeAddressForm
-    }
+      "claims" => {
+        "claim-school" => ClaimSchoolForm,
+        "qualification-details" => QualificationDetailsForm,
+        "qts-year" => QtsYearForm,
+        "subjects-taught" => SubjectsTaughtForm,
+        "still-teaching" => StillTeachingForm,
+        "leadership-position" => LeadershipPositionForm,
+        "mostly-performed-leadership-duties" => MostlyPerformedLeadershipDutiesForm,
+        "reset-claim" => ResetClaimForm,
+        "postcode-search" => PostcodeSearchForm,
+        "select-claim-school" => SelectClaimSchoolForm,
+        "select-home-address" => SelectHomeAddressForm
+      }
+    }.freeze
   end
 end
diff --git a/app/models/reminder.rb b/app/models/reminder.rb
index b819dd8591..08a69a5359 100644
--- a/app/models/reminder.rb
+++ b/app/models/reminder.rb
@@ -2,17 +2,6 @@ class Reminder < ApplicationRecord
   attribute :sent_one_time_password_at, :datetime
   attribute :one_time_password, :string, limit: 6
 
-  validates :full_name, on: [:"personal-details"], presence: {message: "Enter full name"}
-  validates :full_name, length: {maximum: 100, message: "Full name must be 100 characters or less"}
-
-  validates :email_address, on: [:"personal-details"], presence: {message: "Enter an email address"}
-  validates :email_address, format: {with: Rails.application.config.email_regexp, message: "Enter an email address in the correct format, like name@example.com"},
-    length: {maximum: 256, message: "Email address must be 256 characters or less"}, if: -> { email_address.present? }
-
-  validate :otp_validate, on: [:"email-verification"]
-
-  before_save :normalise_one_time_password, if: :one_time_password_changed?
-
   scope :email_verified, -> { where(email_verified: true) }
   scope :not_yet_sent, -> { where(email_sent_at: nil) }
   scope :inside_academic_year, -> { where(itt_academic_year: AcademicYear.current.to_s) }
@@ -35,22 +24,4 @@ def itt_academic_year
       read_attribute(:itt_academic_year)
     )
   end
-
-  def add_invalid_email_error(msg)
-    errors.add(:email_address, :invalid, message: msg)
-  end
-
-  def normalise_one_time_password
-    self.one_time_password = one_time_password.gsub(/\D/, "")
-  end
-
-  def otp_validate
-    return write_attribute(:email_verified, true) if otp.valid?
-
-    errors.add(:one_time_password, otp.warning)
-  end
-
-  def otp
-    @otp ||= OneTimePassword::Validator.new(one_time_password, sent_one_time_password_at)
-  end
 end
diff --git a/app/views/additional_payments/reminders/_one_time_password.html.erb b/app/views/additional_payments/reminders/_one_time_password.html.erb
index 969236c4c7..4dfe9fbd26 100644
--- a/app/views/additional_payments/reminders/_one_time_password.html.erb
+++ b/app/views/additional_payments/reminders/_one_time_password.html.erb
@@ -1,25 +1,25 @@
 <div class="govuk-grid-row">
   <div class="govuk-grid-column-two-thirds">
-    <%= render("shared/error_summary", instance: current_reminder) if current_reminder.errors.any? %>
+    <%= render("shared/error_summary", instance: @form) if @form.errors.any? %>
 
     <span class="govuk-caption-xl">Email verification</span>
 
-    <%= form_for current_reminder, url: reminder_path(current_journey_routing_name) do |form| %>
-      <%= form_group_tag current_reminder do %>
+    <%= form_for @form, url: reminder_path(current_journey_routing_name) do |f| %>
+      <%= form_group_tag @form do %>
         <h1 class="govuk-label-wrapper">
-          <label class="govuk-label govuk-label--l" for="claim_one_time_password"><%= t("one_time_password.title") %></label>
+          <label class="govuk-label govuk-label--l" for="form_one_time_password"><%= t("one_time_password.title") %></label>
         </h1>
 
         <div id="one-time-password-hint" class="govuk-hint">
-          <%= t("one_time_password.hint1_html", email_or_mobile_message: "an email", email_or_mobile_value: current_reminder.email_address) %>
+          <%= t("one_time_password.hint1_html", email_or_mobile_message: "an email", email_or_mobile_value: @form.email_address) %>
           <br><br>
           <%= t("one_time_password.validity_duration", duration_valid: one_time_password_validity_duration) %>
         </div>
 
-        <%= errors_tag current_reminder, :one_time_password %>
-        <%= form.text_field :one_time_password,
+        <%= errors_tag @form, :one_time_password %>
+        <%= f.text_field :one_time_password,
                             autocomplete: "off",
-                            class: css_classes_for_input(current_reminder, :one_time_password, 'govuk-input--width-5'),
+                            class: css_classes_for_input(@form, :one_time_password, 'govuk-input--width-5'),
                             "aria-describedby" => "one-time-password-hint" %>
       <% end %>
 
@@ -28,7 +28,7 @@
       </div>
 
       <div class="govuk-button-group">
-        <%= form.submit "Confirm", class: "govuk-button" %>
+        <%= f.submit "Confirm", class: "govuk-button" %>
         <%= link_to "Change email address", new_reminder_path, class: "govuk-button govuk-button--secondary", role: "button", data: {module: "govuk-button"} %>
       </div>
     <% end %>
diff --git a/app/views/additional_payments/reminders/email_verification.html.erb b/app/views/additional_payments/reminders/email_verification.html.erb
index 11d4e4d3d8..8e8a5e52e3 100644
--- a/app/views/additional_payments/reminders/email_verification.html.erb
+++ b/app/views/additional_payments/reminders/email_verification.html.erb
@@ -1,3 +1,3 @@
-<% content_for(:page_title, page_title(t("one_time_password.title"), journey: current_journey_routing_name, show_error: current_reminder.errors.any?)) %>
+<% content_for(:page_title, page_title(t("one_time_password.title"), journey: current_journey_routing_name, show_error: @form.errors.any?)) %>
 
-<%= render partial: "reminders/one_time_password", locals: {current_reminder: current_reminder, current_journey_routing_name: current_journey_routing_name} %>
+<%= render partial: "reminders/one_time_password", locals: {current_journey_routing_name: current_journey_routing_name} %>
diff --git a/app/views/additional_payments/reminders/personal_details.html.erb b/app/views/additional_payments/reminders/personal_details.html.erb
index 0adeaabd39..e024de195f 100644
--- a/app/views/additional_payments/reminders/personal_details.html.erb
+++ b/app/views/additional_payments/reminders/personal_details.html.erb
@@ -1,25 +1,25 @@
-<% content_for(:page_title, page_title(t("questions.personal_details"), journey: current_journey_routing_name, show_error: current_reminder.errors.any?)) %>
+<% content_for(:page_title, page_title(t("questions.personal_details"), journey: current_journey_routing_name, show_error: @form.errors.any?)) %>
 
 <div class="govuk-grid-row">
   <div class="govuk-grid-column-two-thirds">
-    <%= render("shared/error_summary", instance: current_reminder) if current_reminder.errors.any? %>
+    <%= render("shared/error_summary", instance: @form) if @form.errors.any? %>
 
-    <%= form_for current_reminder, url: reminders_path(current_journey_routing_name) do |form| %>
+    <%= form_for @form, url: reminder_path(current_journey_routing_name) do |f| %>
       <h1 class="govuk-heading-xl">
         <%= t("questions.personal_details") %>
       </h1>
 
-      <%= form_group_tag current_reminder, :full_name do %>
+      <%= form_group_tag @form, :full_name do %>
         <h1 class="govuk-label-wrapper">
-          <%= form.label :full_name, t("additional_payments.reminders.full_name"), {class: "govuk-label govuk-label--l"}  %>
+          <%= f.label :full_name, t("additional_payments.reminders.full_name"), {class: "govuk-label govuk-label--l"}  %>
         </h1>
-        <%= errors_tag current_reminder, :full_name %>
-        <%= form.text_field :full_name, class: css_classes_for_input(current_reminder, :full_name), type: "text", spellcheck: "false", autocomplete: "name" %>
+        <%= errors_tag @form, :full_name %>
+        <%= f.text_field :full_name, class: css_classes_for_input(@form, :full_name), type: "text", spellcheck: "false", autocomplete: "name" %>
       <% end %>
 
-      <%= form_group_tag current_reminder, :email_address do %>
+      <%= form_group_tag @form, :email_address do %>
         <h1 class="govuk-label-wrapper">
-          <%= form.label :email_address, t("questions.email_address"), {class: "govuk-label govuk-label--l"}  %>
+          <%= f.label :email_address, t("questions.email_address"), {class: "govuk-label govuk-label--l"}  %>
         </h1>
         <div class="govuk-hint" id="email_address-hint">
           <p>
@@ -31,8 +31,8 @@
             You can enter the passcode on the next screen.
           </p>
         </div>
-        <%= errors_tag current_reminder, :email_address %>
-         <%= form.text_field :email_address, class: css_classes_for_input(current_reminder, :email_address), type: "text", spellcheck: "false", autocomplete: "email" %>
+        <%= errors_tag @form, :email_address %>
+         <%= f.text_field :email_address, class: css_classes_for_input(@form, :email_address), type: "text", spellcheck: "false", autocomplete: "email" %>
       <% end %>
 
       <details class="govuk-details" data-module="govuk-details">
@@ -47,7 +47,7 @@
         </div>
       </details>
 
-      <%= form.submit "Continue", class: "govuk-button", data: {module: "govuk-button"} %>
+      <%= f.submit "Continue", class: "govuk-button", data: {module: "govuk-button"} %>
     <% end %>
   </div>
 </div>
diff --git a/config/locales/en.yml b/config/locales/en.yml
index fc485e70d9..e8f78a15d7 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -417,6 +417,10 @@ en:
           presence: "Enter an email address"
           format: "Enter an email address in the correct format, like name@example.com"
           length: "Email address must be 256 characters or less"
+      email_verification:
+        errors:
+          one_time_password:
+            invalid: An error occured while validating the passcode, please try generating a new one
       mobile_number:
         errors:
           invalid: "Enter a mobile number, like 07700 900 982 or +44 7700 900 982"
@@ -535,6 +539,17 @@ en:
         errors:
           blank: Select an additional payment
           inclusion: Select a valid additional payment
+      reminders:
+        personal_details:
+          errors:
+            full_name:
+              blank: Enter full name
+              length: Full name must be 100 characters or less
+            email_address:
+              blank: Enter an email address
+              invalid: Enter an email address in the correct format, like name@example.com
+              length: Email address must be 256 characters or less
+              unauthorised: Only authorised email addresses can be used when using a team-only API key
     check_your_answers:
       part_one:
         primary_heading: Check your answers
diff --git a/config/routes.rb b/config/routes.rb
index 5cae21cc67..c0ae7ecca6 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -59,8 +59,8 @@ def matches?(request)
     end
 
     scope constraints: {journey: "additional-payments"} do
-      get "reminders/personal-details", as: :new_reminder, to: "journeys/additional_payments_for_teaching/reminders#new"
-      post "reminders/personal-details", as: :reminders, to: "journeys/additional_payments_for_teaching/reminders#create"
+      get "reminder", as: :new_reminder, to: "journeys/additional_payments_for_teaching/reminders#new"
+      post "reminders/:slug", constraints: {slug: %r{#{Journeys::AdditionalPaymentsForTeaching::SlugSequence::REMINDER_SLUGS.join("|")}}}, defaults: {slug: "personal-details"}, as: :reminders, to: "journeys/additional_payments_for_teaching/reminders#create"
       resources :reminders, only: [:show, :update], param: :slug, constraints: {slug: %r{#{Journeys::AdditionalPaymentsForTeaching::SlugSequence::REMINDER_SLUGS.join("|")}}}, controller: "journeys/additional_payments_for_teaching/reminders"
     end
 
diff --git a/spec/features/reminders_spec.rb b/spec/features/reminders_spec.rb
index f6e9cdfbd9..16be3353d9 100644
--- a/spec/features/reminders_spec.rb
+++ b/spec/features/reminders_spec.rb
@@ -62,7 +62,7 @@
           fill_in "Full name", with: "David Tau"
           fill_in "Email address", with: "david.tau1988@hotmail.co.uk"
           click_on "Continue"
-          fill_in "reminder_one_time_password", with: get_otp_from_email
+          fill_in "form_one_time_password", with: get_otp_from_email
           click_on "Confirm"
           reminder = Reminder.order(:created_at).last
 
@@ -140,7 +140,7 @@
           expect(page).to have_text("Personal details")
           click_on "Continue"
 
-          fill_in "reminder_one_time_password", with: get_otp_from_email
+          fill_in "form_one_time_password", with: get_otp_from_email
           click_on "Confirm"
           reminder = Reminder.order(:created_at).last
 
diff --git a/spec/features/trainee_teacher_subjourney_for_lup_schools_spec.rb b/spec/features/trainee_teacher_subjourney_for_lup_schools_spec.rb
index dae15820e1..2d603472ed 100644
--- a/spec/features/trainee_teacher_subjourney_for_lup_schools_spec.rb
+++ b/spec/features/trainee_teacher_subjourney_for_lup_schools_spec.rb
@@ -41,7 +41,7 @@
     fill_in "Full name", with: "David Tau"
     fill_in "Email address", with: "david.tau1988@hotmail.co.uk"
     click_on "Continue"
-    fill_in "reminder_one_time_password", with: get_otp_from_email
+    fill_in "form_one_time_password", with: get_otp_from_email
     click_on "Confirm"
     reminder = Reminder.order(:created_at).last
 
@@ -76,7 +76,7 @@
     fill_in "Full name", with: "David Tau"
     fill_in "Email address", with: "david.tau1988@hotmail.co.uk"
     click_on "Continue"
-    fill_in "reminder_one_time_password", with: get_otp_from_email
+    fill_in "form_one_time_password", with: get_otp_from_email
     click_on "Confirm"
     reminder = Reminder.order(:created_at).last
 
diff --git a/spec/forms/email_verification_form_spec.rb b/spec/forms/email_verification_form_spec.rb
index 57de0f4851..3d5c58f25a 100644
--- a/spec/forms/email_verification_form_spec.rb
+++ b/spec/forms/email_verification_form_spec.rb
@@ -74,6 +74,12 @@
           it { is_expected.not_to be_valid }
         end
 
+        context "when the code generation timestamp is missing" do
+          let(:one_time_password) { OneTimePassword::Generator.new.code }
+          let(:sent_one_time_password_at) { nil }
+          it { is_expected.not_to be_valid }
+        end
+
         context "when correct code" do
           let(:one_time_password) { OneTimePassword::Generator.new.code }
           let(:sent_one_time_password_at) { Time.now }
diff --git a/spec/forms/form_spec.rb b/spec/forms/form_spec.rb
index 601a8fdd74..f564a7d126 100644
--- a/spec/forms/form_spec.rb
+++ b/spec/forms/form_spec.rb
@@ -139,12 +139,7 @@ def initialize(claim, journey_session)
   end
 
   describe "#persisted?" do
-    before do
-      allow(claim).to receive(:persisted?)
-      form.persisted?
-    end
-
-    it { expect(claim).to have_received(:persisted?) }
+    it { expect(form.persisted?).to eq(true) }
   end
 
   describe "#update!" do
diff --git a/spec/forms/journeys/additional_payments_for_teaching/reminders/email_verification_form_spec.rb b/spec/forms/journeys/additional_payments_for_teaching/reminders/email_verification_form_spec.rb
new file mode 100644
index 0000000000..78bc8ce8d3
--- /dev/null
+++ b/spec/forms/journeys/additional_payments_for_teaching/reminders/email_verification_form_spec.rb
@@ -0,0 +1,44 @@
+require "rails_helper"
+
+RSpec.describe Journeys::AdditionalPaymentsForTeaching::Reminders::EmailVerificationForm do
+  subject(:form) { described_class.new(claim: form_data_object, journey:, journey_session:, params:) }
+
+  let(:journey) { Journeys::AdditionalPaymentsForTeaching }
+  let(:journey_session) { build(:journeys_session, journey: journey::ROUTING_NAME) }
+  let(:form_data_object) { Reminder.new }
+  let(:slug) { "email-verification" }
+  let(:params) { ActionController::Parameters.new({slug:, form: form_params}) }
+  let(:form_params) { {one_time_password: "123456"} }
+
+  it { is_expected.to be_a(EmailVerificationForm) }
+
+  describe ".model_name" do
+    it { expect(form.model_name).to eq(ActiveModel::Name.new(Form)) }
+  end
+
+  describe "#save" do
+    subject(:save) { form.save }
+
+    before do
+      allow(form).to receive(:update!).and_return(true)
+    end
+
+    context "valid params" do
+      let(:form_params) { {"one_time_password" => OneTimePassword::Generator.new.code, "sent_one_time_password_at" => Time.now} }
+
+      it "saves the attributes" do
+        expect(save).to eq(true)
+        expect(form).to have_received(:update!).with(email_verified: true)
+      end
+    end
+
+    context "invalid params" do
+      let(:form_params) { {"one_time_password" => OneTimePassword::Generator.new.code, "sent_one_time_password_at" => ""} }
+
+      it "does not save the attributes" do
+        expect(save).to eq(false)
+        expect(form).not_to have_received(:update!)
+      end
+    end
+  end
+end
diff --git a/spec/forms/journeys/additional_payments_for_teaching/reminders/personal_details_form_spec.rb b/spec/forms/journeys/additional_payments_for_teaching/reminders/personal_details_form_spec.rb
new file mode 100644
index 0000000000..57a14906cd
--- /dev/null
+++ b/spec/forms/journeys/additional_payments_for_teaching/reminders/personal_details_form_spec.rb
@@ -0,0 +1,55 @@
+require "rails_helper"
+
+RSpec.describe Journeys::AdditionalPaymentsForTeaching::Reminders::PersonalDetailsForm, type: :model do
+  subject(:form) { described_class.new(claim: form_data_object, journey:, journey_session:, params:) }
+
+  let(:journey) { Journeys::AdditionalPaymentsForTeaching }
+  let(:journey_session) { build(:journeys_session, journey: journey::ROUTING_NAME) }
+  let(:form_data_object) { Reminder.new }
+  let(:slug) { "personal-details" }
+  let(:params) { ActionController::Parameters.new({slug:, form: form_params}) }
+  let(:form_params) { {full_name: "John Doe"} }
+
+  it { is_expected.to be_a(Form) }
+
+  describe "validations" do
+    it { is_expected.to validate_presence_of(:full_name).with_message(form.i18n_errors_path(:"full_name.blank")) }
+    it { is_expected.to validate_length_of(:full_name).is_at_most(100).with_message(form.i18n_errors_path(:"full_name.length")) }
+
+    it { is_expected.to validate_presence_of(:email_address).with_message(form.i18n_errors_path(:"email_address.blank")) }
+    it { is_expected.to validate_length_of(:email_address).is_at_most(256).with_message(form.i18n_errors_path(:"email_address.length")) }
+
+    it { is_expected.to allow_value("valid@email.com").for(:email_address) }
+    it { is_expected.not_to allow_value("in valid@email.com").for(:email_address) }
+  end
+
+  describe ".model_name" do
+    it { expect(form.model_name).to eq(ActiveModel::Name.new(Form)) }
+  end
+
+  describe "#save" do
+    subject(:save) { form.save }
+
+    before do
+      allow(form).to receive(:update!).and_return(true)
+    end
+
+    context "valid params" do
+      let(:form_params) { {"full_name" => "John Doe", "email_address" => "john.doe@email.com"} }
+
+      it "saves the attributes" do
+        expect(save).to eq(true)
+        expect(form).to have_received(:update!).with(form_params)
+      end
+    end
+
+    context "invalid params" do
+      let(:form_params) { {"full_name" => "John Doe", "email_address" => ""} }
+
+      it "does not save the attributes" do
+        expect(save).to eq(false)
+        expect(form).not_to have_received(:update!)
+      end
+    end
+  end
+end
diff --git a/spec/models/reminder_spec.rb b/spec/models/reminder_spec.rb
index 5ac5563744..b89e1314c0 100644
--- a/spec/models/reminder_spec.rb
+++ b/spec/models/reminder_spec.rb
@@ -1,36 +1,6 @@
 require "rails_helper"
 
 RSpec.describe Reminder, type: :model do
-  context "that has a email address" do
-    it "validates that the value is in the correct format" do
-      expect(build(:reminder, email_address: "notan email@address.com")).not_to be_valid
-      expect(build(:reminder, email_address: "david.tau.2020.gb@example.com")).to be_valid
-      expect(build(:reminder, email_address: "name@example")).not_to be_valid
-    end
-
-    it "checks that the email address in not longer than 256 characters" do
-      expect(build(:reminder, email_address: "#{"e" * 256}@example.com")).not_to be_valid
-    end
-  end
-
-  context "that has a full name" do
-    it "validates the length of name is 100 characters or less" do
-      expect(build(:reminder, full_name: "Name " * 50)).not_to be_valid
-      expect(build(:reminder, full_name: "John")).to be_valid
-    end
-  end
-
-  context "when saving in the 'personal-details' validation context" do
-    it "validates the presence of full_name" do
-      expect(build(:reminder, full_name: nil)).not_to be_valid(:"personal-details")
-      expect(build(:reminder, full_name: "Miss Sveta Bond-Areemev")).to be_valid(:"personal-details")
-    end
-
-    it "validates the presence of email_address" do
-      expect(build(:reminder, email_address: nil)).not_to be_valid(:"personal-details")
-    end
-  end
-
   describe ".to_be_sent" do
     let(:count) { [*1..5].sample }
     let(:email_sent_at) { nil }
diff --git a/spec/requests/form_submittable_spec.rb b/spec/requests/form_submittable_spec.rb
new file mode 100644
index 0000000000..6609ff5770
--- /dev/null
+++ b/spec/requests/form_submittable_spec.rb
@@ -0,0 +1,186 @@
+require "rails_helper"
+
+class TestDummyController < BasePublicController
+  include PartOfClaimJourney
+  include FormSubmittable
+
+  # Overriding template for current slug to bypass view search
+  def render_template_for_current_slug
+    render plain: "Rendered template for current slug: #{current_slug}"
+  end
+
+  skip_before_action :send_unstarted_claimants_to_the_start
+
+  def slugs
+    %w[first-slug second-slug]
+  end
+
+  def next_slug
+    slugs[current_slug_index + 1]
+  end
+
+  def current_slug
+    slugs[current_slug_index]
+  end
+
+  def current_slug_index
+    slugs.index(params[:slug]) || 0
+  end
+end
+
+class TestDummyForm < Form
+  def save
+  end
+end
+
+RSpec.describe FormSubmittable, type: :request do
+  before do
+    Rails.application.routes.draw do
+      scope path: ":journey", constraints: {journey: "additional-payments"} do
+        get "/claim", to: "test_dummy#new"
+        get "/:slug", as: :test_dummy, to: "test_dummy#show"
+        post "/:slug", to: "test_dummy#create", as: :test_dummies
+        patch "/:slug", to: "test_dummy#update"
+      end
+    end
+  end
+
+  after { Rails.application.reload_routes! }
+
+  before { create(:journey_configuration, :additional_payments) }
+
+  shared_context :define_filter do |filter_name|
+    before { define_filter(filter_name) }
+    after { remove_filter(filter_name) }
+
+    def define_filter(filter_name)
+      TestDummyController.class_eval do
+        define_method(filter_name) do
+          render plain: "Triggered: `#{filter_name}` filter"
+        end
+      end
+    end
+
+    def remove_filter(filter_name)
+      TestDummyController.class_eval do
+        remove_method(filter_name) if method_defined?(filter_name)
+      end
+    end
+  end
+
+  describe "GET #new" do
+    it "redirects to the first slug" do
+      get "/additional-payments/claim"
+      expect(response).to redirect_to("/additional-payments/first-slug")
+    end
+  end
+
+  describe "GET #show" do
+    context "when the `{current_slug}_before_show` filter is defined" do
+      include_context :define_filter, :first_slug_before_show
+
+      it "executes the filter" do
+        get "/additional-payments/first-slug"
+        expect(response.body).to include("Triggered: `first_slug_before_show` filter")
+      end
+    end
+
+    context "when the `{current_slug}_before_show` filter is not defined" do
+      it "renders the template for the current slug" do
+        get "/additional-payments/first-slug"
+        expect(response.body).to include("Rendered template for current slug: first-slug")
+      end
+    end
+  end
+
+  shared_examples :form_submission do
+    def submit(slug)
+      send(method, slug, params: {})
+    end
+
+    context "when a form object is not present for the current slug" do
+      context "when the `{current_slug}_before_update` filter is not defined" do
+        it "redirects to the next slug" do
+          submit "/additional-payments/first-slug"
+          expect(response).to redirect_to("/additional-payments/second-slug")
+        end
+      end
+
+      context "when the `{current_slug}_before_update` filter is defined" do
+        include_context :define_filter, :first_slug_before_update
+
+        it "executes the filter" do
+          submit "/additional-payments/first-slug"
+          expect(response.body).to include("Triggered: `first_slug_before_update` filter")
+        end
+      end
+    end
+
+    context "when a form object is present for the current slug" do
+      before do
+        stub_const("Journeys::AdditionalPaymentsForTeaching::FORMS",
+          {"test_dummy" => {"first-slug" => TestDummyForm, "second-slug" => TestDummyForm}})
+      end
+
+      context "when the form save succeeds" do
+        before do
+          allow_any_instance_of(TestDummyForm).to receive(:save).and_return(true)
+        end
+
+        context "when the `{current_slug}_after_form_save_success` filter is defined" do
+          include_context :define_filter, :first_slug_after_form_save_success
+
+          it "executes the filter" do
+            submit "/additional-payments/first-slug"
+            expect(response.body).to include("Triggered: `first_slug_after_form_save_success` filter")
+          end
+        end
+
+        context "when the `{current_slug}_after_form_save_success` filter is not defined" do
+          it "redirects to the next slug" do
+            submit "/additional-payments/first-slug"
+            expect(response).to redirect_to("/additional-payments/second-slug")
+          end
+        end
+
+        context "when it's the end of the sequence" do
+          it { expect { submit "/additional-payments/second-slug" }.to raise_error(NoMethodError, /End of sequence/) }
+        end
+      end
+
+      context "when the form save fails" do
+        before do
+          allow_any_instance_of(TestDummyForm).to receive(:save).and_return(false)
+        end
+
+        context "when the `{current_slug}_after_form_save_failure` filter is defined" do
+          include_context :define_filter, :first_slug_after_form_save_failure
+
+          it "executes the filter" do
+            submit "/additional-payments/first-slug"
+            expect(response.body).to include("Triggered: `first_slug_after_form_save_failure` filter")
+          end
+        end
+
+        context "when the `{current_slug}_after_form_save_failure` filter is not defined" do
+          it "renders to template for the current slug" do
+            submit "/additional-payments/second-slug"
+            expect(response.body).to include("Rendered template for current slug: second-slug")
+          end
+        end
+      end
+    end
+  end
+
+  describe "POST #create" do
+    let(:method) { :post }
+
+    it_behaves_like :form_submission
+  end
+
+  describe "PATCH #update" do
+    let(:method) { :patch }
+
+    it_behaves_like :form_submission
+  end
+end
diff --git a/spec/requests/reminders_spec.rb b/spec/requests/reminders_spec.rb
index 11f2114ed7..60977342a4 100644
--- a/spec/requests/reminders_spec.rb
+++ b/spec/requests/reminders_spec.rb
@@ -4,10 +4,14 @@
   before { create(:journey_configuration, :additional_payments) }
 
   describe "#create" do
+    before do
+      allow_any_instance_of(BasePublicController).to receive(:current_claim).and_return(current_claim)
+    end
+    let(:current_claim) { create(:claim, policy: Policies::LevellingUpPremiumPayments) }
     let(:submit_form) { post reminders_path("additional-payments", params: form_params) }
 
     context "with full name and valid email address" do
-      let(:form_params) { {reminder: {full_name: "Joe Bloggs", email_address: "joe.bloggs@example.com"}} }
+      let(:form_params) { {form: {full_name: "Joe Bloggs", email_address: "joe.bloggs@example.com"}} }
 
       it "redirects to /email-verfication slug" do
         submit_form
@@ -16,7 +20,7 @@
     end
 
     context "with empty form" do
-      let(:form_params) { {reminder: {full_name: "", email_address: ""}} }
+      let(:form_params) { {form: {full_name: "", email_address: ""}} }
 
       before { submit_form }
 
@@ -30,7 +34,7 @@
     end
 
     context "invalid email address" do
-      let(:form_params) { {reminder: {full_name: "Joe Bloggs", email_address: "joe.bloggs.example.com"}} }
+      let(:form_params) { {form: {full_name: "Joe Bloggs", email_address: "joe.bloggs.example.com"}} }
 
       it "renders errors containing invalid email address" do
         submit_form
@@ -39,7 +43,7 @@
     end
 
     context "Notify returns an error about email address is required" do
-      let(:form_params) { {reminder: {full_name: "Joe Bloggs", email_address: "joe.bloggs@example.com"}} }
+      let(:form_params) { {form: {full_name: "Joe Bloggs", email_address: "joe.bloggs@example.com"}} }
 
       let(:mailer) { double("notify") }
       let(:notifications_error_response) { double("response", code: 400, body: "ValidationError: email_address is a required property") }
@@ -56,7 +60,7 @@
     end
 
     context "Notify returns an error about team only API key" do
-      let(:form_params) { {reminder: {full_name: "Joe Bloggs", email_address: "joe.bloggs@example.com"}} }
+      let(:form_params) { {form: {full_name: "Joe Bloggs", email_address: "joe.bloggs@example.com"}} }
 
       let(:mailer) { double("notify") }
       let(:notifications_error_response) { double("response", code: 400, body: "BadRequestError: Can’t send to this recipient using a team-only API key") }
@@ -73,7 +77,7 @@
     end
 
     context "Notify returns an unknown error" do
-      let(:form_params) { {reminder: {full_name: "Joe Bloggs", email_address: "joe.bloggs@example.com"}} }
+      let(:form_params) { {form: {full_name: "Joe Bloggs", email_address: "joe.bloggs@example.com"}} }
 
       let(:mailer) { double("notify") }
       let(:notifications_error_response) { double("response", code: 400, body: "Something unexpected") }