diff --git a/.github/workflows/build-and-test-differential.yaml b/.github/workflows/build-and-test-differential.yaml
index 6b15aa4b3..dbb5bed34 100644
--- a/.github/workflows/build-and-test-differential.yaml
+++ b/.github/workflows/build-and-test-differential.yaml
@@ -207,7 +207,7 @@ jobs:
         with:
           fetch-depth: 0
           # This repo checkout is only for .github workflow definitions. Use the feature branch's version as it might contain updated functionality.
-          ref: ${{ github.head_ref }}
+          ref: ${{ github.event.pull_request.head.sha }}
           sparse-checkout-cone-mode: false
           sparse-checkout: |
             .github/