diff --git a/.github/workflows/version.yaml b/.github/workflows/version.yaml
index 82ccb05077..6e32d9e148 100644
--- a/.github/workflows/version.yaml
+++ b/.github/workflows/version.yaml
@@ -17,4 +17,4 @@ jobs:
         uses: actions/checkout@v2
       - name: Check version number
         run: |
-          python3 ci/check_version_number.py --branch ${{ env.GITHUB_BASE_REF }}
+          python3 ci/check_version_number.py --branch ${{ github.base_ref }}