--- a/taskcluster/ci/source-test/python-tests.yml
+++ b/taskcluster/ci/source-test/python-tests.yml
@@ -75,19 +75,19 @@ mozbase:
     when:
         files-changed:
             - 'testing/mozbase/**'
             - 'config/mozunit.py'
             - 'python/mach_commands.py'
 
 mozharness:
     description: mozharness integration tests
-    platform: lint/opt
+    platform: linux64/opt
     treeherder:
-        symbol: py(MH)
+        symbol: py(mh)
         kind: test
         tier: 2
     worker-type: aws-provisioner-v1/gecko-t-linux-xlarge
     worker:
         docker-image: {in-tree: "lint"}
         max-run-time: 1800
     run:
         using: run-task