diff --git a/.github/workflows/dry-run.yml b/.github/workflows/dry-run.yml
index fff2a2477..d40b05cf0 100644
--- a/.github/workflows/dry-run.yml
+++ b/.github/workflows/dry-run.yml
@@ -18,15 +18,14 @@ on:
     types:
       - completed
 
-concurrency:
-  # Only run this once at a time on any given PR
-  group: dry-run-${{ github.event.workflow_run.pull_requests[0].number }}
-  cancel-in-progress: true
-
 jobs:
   dry-run:
     runs-on: ubuntu-latest
     if: ${{ github.event.workflow_run.conclusion == 'success' && github.event.workflow_run.event == 'pull_request' }}
+    concurrency:
+      # Only run this once at a time on any given PR
+      group: dry-run-${{ github.event.workflow_run.head_branch }}
+      cancel-in-progress: true
     permissions:
       pull-requests: write
     steps: