diff --git a/.github/workflows/live.yml b/.github/workflows/live.yml
index 206d0d66..ae5c8f28 100644
--- a/.github/workflows/live.yml
+++ b/.github/workflows/live.yml
@@ -20,9 +20,10 @@ on:
 
 # A newer run of the same trigger supersedes an in-flight one, and cancelling
 # saves the calls it has not made yet (providers bill per call). Grouping by
-# trigger keeps a merge from cancelling a manual `all` run, or the reverse.
+# trigger keeps a merge from cancelling a manual `all` run, or the reverse;
+# grouping by branch keeps a push to release/2.1 from cancelling main's run.
 concurrency:
-  group: live-tests-${{ github.event_name }}
+  group: live-tests-${{ github.event_name }}-${{ github.ref }}
   cancel-in-progress: true
 
 jobs: