--- a/taskcluster/taskgraph/transforms/partials.py
+++ b/taskcluster/taskgraph/transforms/partials.py
@@ -142,19 +142,23 @@ def make_task_description(config, jobs):
 
         task = {
             'label': label,
             'description': "{} Partials".format(
                 dep_job.task["metadata"]["description"]),
             'worker-type': 'aws-provisioner-v1/gecko-%s-b-linux' % level,
             'dependencies': dependencies,
             'scopes': [
-                'secrets:get:project/releng/gecko/build/level-%s/datadog-api-key' % level,
-                'auth:aws-s3:read-write:tc-gp-private-1d-us-east-1/releng/mbsdiff-cache/'
+                'secrets:get:project/releng/gecko/build/level-%s/datadog-api-key' % level
             ],
             'attributes': attributes,
             'run-on-projects': dep_job.attributes.get('run_on_projects'),
             'treeherder': treeherder,
             'extra': extra,
             'worker': worker,
         }
 
+        # We only want caching on linux/windows due to bug 1436977
+        if any([platform in dep_th_platform for platform in ['linux', 'windows']]):
+            task['scopes'].append(
+                'auth:aws-s3:read-write:tc-gp-private-1d-us-east-1/releng/mbsdiff-cache/')
+
         yield task