diff --git a/.taskcluster.yml b/.taskcluster.yml
index 6e5c23d12..58030252d 100644
--- a/.taskcluster.yml
+++ b/.taskcluster.yml
@@ -15,12 +15,18 @@ tasks:
     head_branch:
       $if: 'tasks_for == "github-pull-request"'
       then: ${event.pull_request.head.ref}
-      else: ${event.release.target_commitish}
+      else:
+        $if: 'tasks_for == "github-push"'
+        then: ${event.ref}
+        else: ${event.release.target_commitish}
 
     head_rev:
       $if: 'tasks_for == "github-pull-request"'
       then: ${event.pull_request.head.sha}
-      else: ${event.release.tag_name}
+      else:
+        $if: 'tasks_for == "github-push"'
+        then: ${event.after}
+        else: ${event.release.tag_name}
 
     repository:
       $if: 'tasks_for == "github-pull-request"'
diff --git a/automation/taskcluster/decision_task_nightly.py b/automation/taskcluster/decision_task_nightly.py
index 3573c17ae..8da2a1497 100644
--- a/automation/taskcluster/decision_task_nightly.py
+++ b/automation/taskcluster/decision_task_nightly.py
@@ -25,7 +25,7 @@
     owner="android-components-team@mozilla.com",
     source='{}/raw/{}/.taskcluster.yml'.format(GITHUB_HTTP_REPOSITORY, HEAD_REV),
     scheduler_id=SCHEDULER_ID,
-    build_worker_type=BUILD_WORKER_TYPE,
+    build_worker_type=os.environ.get('BUILD_WORKER_TYPE'),
 )