diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index aac8522..b5514fa 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -41,12 +41,15 @@ jobs:
       # release PR here. outputs.pr is set whenever the release PR was created
       # OR updated, so this re-runs on every push to main while a release PR is
       # open — adding an already-present assignee is a no-op, so that's safe.
+      # The PR is selected by release-please's deterministic head branch, NOT
+      # fromJson(outputs.pr).number: step env templates are evaluated even when
+      # if: is false, so fromJson('') on a no-release push fails the whole job
+      # and skips publish (LAB-865).
       - name: Assign release PR to 27Bslash6
         if: ${{ steps.release.outputs.pr }}
-        run: gh pr edit "$PR_NUMBER" --repo "$GITHUB_REPOSITORY" --add-assignee 27Bslash6
+        run: gh pr edit "release-please--branches--main--components--cachekit-core" --repo "$GITHUB_REPOSITORY" --add-assignee 27Bslash6
         env:
           GH_TOKEN: ${{ steps.app-token.outputs.token }}
-          PR_NUMBER: ${{ fromJson(steps.release.outputs.pr).number }}
 
   publish:
     needs: release-please