diff --git a/AwsCryptographicMaterialProviders/codebuild/release-python/prod-release.yml b/AwsCryptographicMaterialProviders/codebuild/release-python/prod-release.yml
index f9774dd07..3184f2cfd 100644
--- a/AwsCryptographicMaterialProviders/codebuild/release-python/prod-release.yml
+++ b/AwsCryptographicMaterialProviders/codebuild/release-python/prod-release.yml
@@ -28,6 +28,15 @@ phases:
       - git fetch --tags
       - git checkout $COMMIT_ID
       - FOUND_VERSION=$(sed -n 's/version = "\(.*\)"/\1/p' AwsCryptographicMaterialProviders/runtimes/python/pyproject.toml)
+      # Assert we are not releasing "aws-cryptographic-material-providers==10.0.0" to prod PyPI.
+      # A bad release has already been uploaded under this name/version to prod PyPI.
+      # This release has been deleted.
+      # Prod PyPI does not allow re-uploading a release under the same name/version.
+      - |
+        if expr ${FOUND_VERSION} == "10.0.0"; then
+          echo "Cannot release version 10.0.0"
+          exit 1;
+        fi
       - |
         if expr ${FOUND_VERSION} != ${VERSION}; then
           echo "pyproject.toml version (${FOUND_VERSION}) does not match expected version (${VERSION}), stopping"
diff --git a/AwsCryptographicMaterialProviders/codebuild/release-python/test-release.yml b/AwsCryptographicMaterialProviders/codebuild/release-python/test-release.yml
index 38517065a..d672c0f3e 100644
--- a/AwsCryptographicMaterialProviders/codebuild/release-python/test-release.yml
+++ b/AwsCryptographicMaterialProviders/codebuild/release-python/test-release.yml
@@ -28,6 +28,16 @@ phases:
       - git fetch --tags
       - git checkout $COMMIT_ID
       - FOUND_VERSION=$(sed -n 's/version = "\(.*\)"/\1/p' AwsCryptographicMaterialProviders/runtimes/python/pyproject.toml)
+      # Assert we are not releasing "aws-cryptographic-material-providers==10.0.0" to prod PyPI.
+      # A bad release has already been uploaded under this name/version to prod PyPI.
+      # This release has been deleted.
+      # Prod PyPI does not allow re-uploading a release under the same name/version.
+      # (We do not need this assertion for other libraries in the MPL; this only applies to "aws-cryptographic-material-providers==10.0.0".)
+      - |
+        if expr ${FOUND_VERSION} == "10.0.0"; then
+          echo "Cannot release version 10.0.0"
+          exit 1;
+        fi
       - |
         if expr ${FOUND_VERSION} != ${VERSION}; then
           echo "pyproject.toml version (${FOUND_VERSION}) does not match expected version (${VERSION}), stopping"
diff --git a/AwsCryptographicMaterialProviders/codebuild/release-python/validate.yml b/AwsCryptographicMaterialProviders/codebuild/release-python/validate.yml
index 9ff7aac5a..a727dbb8d 100644
--- a/AwsCryptographicMaterialProviders/codebuild/release-python/validate.yml
+++ b/AwsCryptographicMaterialProviders/codebuild/release-python/validate.yml
@@ -38,7 +38,7 @@ phases:
       # The actual test code must be from local, since we don't publish tests.
       - pip install aws-cryptographic-material-providers==$VERSION
       # Install ESDK-Python, override its requirements to force use of the just-published MPL version
-      - git clone -b mpl-reviewed https://github.com/aws/aws-encryption-sdk-python.git
+      - git clone -b master https://github.com/aws/aws-encryption-sdk-python.git
       - cd aws-encryption-sdk-python
       - sed -i "s/aws-cryptographic-material-providers.*/aws-cryptographic-material-providers==$VERSION/" requirements_mpl.txt
       - cd ..
diff --git a/ComAmazonawsDynamodb/codebuild/release-python/prod-release.yml b/ComAmazonawsDynamodb/codebuild/release-python/prod-release.yml
index def04e70d..d3691897c 100644
--- a/ComAmazonawsDynamodb/codebuild/release-python/prod-release.yml
+++ b/ComAmazonawsDynamodb/codebuild/release-python/prod-release.yml
@@ -52,12 +52,12 @@ phases:
 batch:
   fast-fail: true
   build-graph:
-    - identifier: release_to_staging
+    - identifier: release_to_prod
       env:
         image: aws/codebuild/standard:7.0
-    - identifier: validate_staging_release
+    - identifier: validate_prod_release
       depend-on:
-        - release_to_staging
+        - release_to_prod
       buildspec: ComAmazonawsDynamodb/codebuild/release-python/validate.yml
       env:
         variables: