--- a/testing/mozharness/configs/builds/branch_specifics.py
+++ b/testing/mozharness/configs/builds/branch_specifics.py
@@ -317,17 +317,17 @@ config = {
         'stage_server': 'upload.ffxbld.productdelivery.prod.mozaws.net',
     },
     'fig': {},
     'graphics': {
         'stage_server': 'upload.ffxbld.productdelivery.prod.mozaws.net',
     },
     # 'holly': {},
     'jamun': {
-        'update_channel': 'release-dev',
+        'update_channel': 'beta-dev',
         'enable_release_promotion': 1,
         'platform_overrides': {
             'linux': {
                 'src_mozconfig': 'browser/config/mozconfigs/linux32/release',
             },
             'linux-debug': {
                 'update_channel': 'default',
             },
@@ -345,17 +345,17 @@ config = {
             },
             'linux64-st-an-debug': {
                 'update_channel': 'default',
             },
             'linux64-st-an': {
                 'update_channel': 'default',
             },
             'macosx64': {
-                'src_mozconfig': 'browser/config/mozconfigs/macosx-universal/release',
+                'src_mozconfig': 'browser/config/mozconfigs/macosx64/release',
             },
             'macosx64-debug': {
                 'update_channel': 'default',
             },
             'macosx64-st-an': {
                 'update_channel': 'default',
             },
             'macosx64-st-an-debug': {