diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 41df476306..6cdf3e1b43 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -30,47 +30,37 @@ jobs:
         # and then use `include` to define their settings.
 
         name: [
-          linux-python2,
-          linux-python2-debug,
           linux-python3,
+          linux-python3-debug,
           windows-python3,
           windows-python3-debug
         ]
 
         include:
 
-          - name: linux-python2
+          - name: linux-python3
             os: ubuntu-20.04
             buildType: RELEASE
             containerImage: ghcr.io/gafferhq/build/build:2.0.0
             options: .github/workflows/main/options.posix
-            dependenciesURL: https://github.com/GafferHQ/dependencies/releases/download/5.1.0/gafferDependencies-5.1.0-Python2-linux.tar.gz
+            dependenciesURL: https://github.com/GafferHQ/dependencies/releases/download/6.0.0/gafferDependencies-6.0.0-linux.tar.gz
             tests: testCore testCorePython testScene testImage testAlembic testUSD testVDB testAppleseed
             publish: true
 
-          - name: linux-python2-debug
+          - name: linux-python3-debug
             os: ubuntu-20.04
             buildType: DEBUG
             containerImage: ghcr.io/gafferhq/build/build:2.0.0
             options: .github/workflows/main/options.posix
-            dependenciesURL: https://github.com/GafferHQ/dependencies/releases/download/5.1.0/gafferDependencies-5.1.0-Python2-linux.tar.gz
+            dependenciesURL: https://github.com/GafferHQ/dependencies/releases/download/6.0.0/gafferDependencies-6.0.0-linux.tar.gz
             tests: testCore testCorePython testScene testImage testAlembic testUSD testVDB testAppleseed
             publish: false
 
-          - name: linux-python3
-            os: ubuntu-20.04
-            buildType: RELEASE
-            containerImage: ghcr.io/gafferhq/build/build:2.0.0
-            options: .github/workflows/main/options.posix
-            dependenciesURL: https://github.com/GafferHQ/dependencies/releases/download/5.1.0/gafferDependencies-5.1.0-Python3-linux.tar.gz
-            tests: testCore testCorePython testScene testImage testAlembic testUSD testVDB testAppleseed
-            publish: true
-
           - name: windows-python3
             os: windows-2019
             buildType: RELEASE
             options: .github/workflows/main/options.windows
-            dependenciesURL: https://github.com/hypothetical-inc/gafferDependencies/releases/download/6.2.1/gafferDependencies-6.2.1-Python3-windows.zip
+            dependenciesURL: https://github.com/GafferHQ/dependencies/releases/download/6.0.0/gafferDependencies-6.0.0-windows.zip
             tests: testCore testCorePython testScene testImage testAlembic testUSD testVDB
             publish: true
 
@@ -78,7 +68,7 @@ jobs:
             os: windows-2019
             buildType: RELWITHDEBINFO
             options: .github/workflows/main/options.windows
-            dependenciesURL: https://github.com/hypothetical-inc/gafferDependencies/releases/download/6.2.1/gafferDependencies-6.2.1-Python3-windows.zip
+            dependenciesURL: https://github.com/GafferHQ/dependencies/releases/download/6.0.0/gafferDependencies-6.0.0-windows.zip
             tests: testCore testCorePython testScene testImage testAlembic testUSD testVDB
             publish: false
 
diff --git a/Changes b/Changes
index 6e3c0da7ff..7de921ec59 100644
--- a/Changes
+++ b/Changes
@@ -1,16 +1,29 @@
-10.4.x.x (relative to 10.4.5.0)
+10.4.6.0 (relative to 10.4.5.0)
 ========
 
+Features
+--------
+
+- MeshAlgo : Added new MeshSplitter class, for efficient splitting meshes based on uniform primitive variables.
+- ImathHash : Added new header that defines `std::hash` for Imath types.
+
 Improvements
 ------------
 
 - PointsPrimitive, Primitive : Accelerated bounds computation using `tbb::parallel_reduce`.
+- MeshAlgo : Improved performance of `segment()`.
 
 Fixes
 -----
 
 - ImageReader : Fixed compilation with versions of OIIO < 2.4.
 - USDScene : Invalid primitive variables are now skipped during loading, with a warning being emitted instead.
+- MeshAlgo : Fixed crease handling in `deleteFaces()`.
+
+Build
+-----
+
+- Updated CI builds to use GafferHQ/dependencies version `6.0.0`, making them suitable for use in Gaffer `1.2.x.x`.
 
 10.4.5.0 (relative to 10.4.4.0)
 ========
diff --git a/SConstruct b/SConstruct
index c3d9a50b32..acc581bc41 100644
--- a/SConstruct
+++ b/SConstruct
@@ -56,7 +56,7 @@ SConsignFile()
 
 ieCoreMilestoneVersion = 10 # for announcing major milestones - may contain all of the below
 ieCoreMajorVersion = 4 # backwards-incompatible changes
-ieCoreMinorVersion = 5 # new backwards-compatible features
+ieCoreMinorVersion = 6 # new backwards-compatible features
 ieCorePatchVersion = 0 # bug fixes
 ieCoreVersionSuffix = "" # used for alpha/beta releases. Example: "a1", "b2", etc.