diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index f660e95..3b2c1ee 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -4,6 +4,13 @@ Release Notes
 v1.0.0-alpha.x
 ---------------
 
+### Breaking changes
+
+- Minimum OpenAssetIO-MediaCreation version increased to v1.0.0-alpha.9
+  for compatibility with the latest OpenAssetIO. See
+  [OpenAssetIO#1311](https://github.com/OpenAssetIO/OpenAssetIO/issues/1311).
+  [#90](https://github.com/OpenAssetIO/OpenAssetIO-Manager-BAL/issues/90)
+
 ### New features
 
 - Added support for configuring the result of `hasCapability(...)`
@@ -24,7 +31,6 @@ v1.0.0-alpha.16
   they are no longer percent decoded before being passed on to the host.
   [#109](https://github.com/OpenAssetIO/OpenAssetIO-Manager-BAL/issues/109)
 
-
 v1.0.0-alpha.15
 ---------------
 
diff --git a/pyproject.toml b/pyproject.toml
index a2b40cd..af9f26b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -5,7 +5,7 @@
 name = "openassetio-manager-bal"
 version = "1.0.0a16"
 requires-python = ">=3.7"
-dependencies = ["openassetio>=1.0.0b2.rev0", "openassetio-mediacreation>=1.0.0a7"]
+dependencies = ["openassetio>=1.0.0b2.rev0", "openassetio-mediacreation>=1.0.0a9"]
 
 authors = [
   { name = "Contributors to the OpenAssetIO project", email = "openassetio-discussion@lists.aswf.io" }