--- a/testing/mozharness/configs/builds/branch_specifics.py
+++ b/testing/mozharness/configs/builds/branch_specifics.py
@@ -33,24 +33,38 @@ config = {
     "mozilla-central": {
         "repo_path": 'mozilla-central',
         "update_channel": "nightly",
         "graph_server_branch_name": "Firefox",
         'use_branch_in_symbols_extra_buildid': False,
         'stage_server': 'upload.ffxbld.productdelivery.prod.mozaws.net',
     },
     'mozilla-release': {
+        'enable_release_promotion': True,
         'repo_path': 'releases/mozilla-release',
-        # TODO I think we can remove update_channel since we don't run
-        # nightlies for mozilla-release
         'update_channel': 'release',
         'branch_uses_per_checkin_strategy': True,
         'use_branch_in_symbols_extra_buildid': False,
         'stage_server': 'upload.ffxbld.productdelivery.prod.mozaws.net',
         'platform_overrides': {
+            'linux': {
+                'src_mozconfig': 'browser/config/mozconfigs/linux32/release',
+            },
+            'linux64': {
+                'src_mozconfig': 'browser/config/mozconfigs/linux64/release',
+            },
+            'macosx64': {
+                'src_mozconfig': 'browser/config/mozconfigs/macosx-universal/release',
+            },
+            'win32': {
+                'src_mozconfig': 'browser/config/mozconfigs/win32/release',
+            },
+            'win64': {
+                'src_mozconfig': 'browser/config/mozconfigs/win64/release',
+            },
             'linux-debug': {
                 'update_channel': 'default',
             },
             'linux64-debug': {
                 'update_channel': 'default',
             },
             'linux64-asan-debug': {
                 'update_channel': 'default',
@@ -91,18 +105,16 @@ config = {
             'win64-debug': {
                 'update_channel': 'default',
             },
         },
     },
     'mozilla-beta': {
         'enable_release_promotion': 1,
         'repo_path': 'releases/mozilla-beta',
-        # TODO I think we can remove update_channel since we don't run
-        # nightlies for mozilla-beta
         'update_channel': 'beta',
         'branch_uses_per_checkin_strategy': True,
         'use_branch_in_symbols_extra_buildid': False,
         'stage_server': 'upload.ffxbld.productdelivery.prod.mozaws.net',
         'platform_overrides': {
             'linux': {
                 'src_mozconfig': 'browser/config/mozconfigs/linux32/beta',
             },

copy from testing/mozharness/configs/single_locale/mozilla-beta.py
copy to testing/mozharness/configs/single_locale/mozilla-release.py
--- a/testing/mozharness/configs/single_locale/mozilla-beta.py
+++ b/testing/mozharness/configs/single_locale/mozilla-release.py
@@ -1,30 +1,30 @@
 config = {
     "nightly_build": True,
-    "branch": "mozilla-beta",
-    "en_us_binary_url": "http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-mozilla-beta/",
-    "update_channel": "beta",
-    "latest_mar_dir": '/pub/mozilla.org/firefox/nightly/latest-mozilla-beta-l10n',
+    "branch": "mozilla-release",
+    "en_us_binary_url": "http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-mozilla-release/",
+    "update_channel": "release",
+    "latest_mar_dir": '/pub/mozilla.org/firefox/nightly/latest-mozilla-release-l10n',
 
     # l10n
-    "hg_l10n_base": "https://hg.mozilla.org/releases/l10n/mozilla-beta",
+    "hg_l10n_base": "https://hg.mozilla.org/releases/l10n/mozilla-release",
 
     # repositories
-    "mozilla_dir": "mozilla-beta",
+    "mozilla_dir": "mozilla-release",
     "repos": [{
         "vcs": "hg",
         "repo": "https://hg.mozilla.org/build/tools",
         "revision": "default",
         "dest": "tools",
     }, {
         "vcs": "hgtool",
-        "repo": "https://hg.mozilla.org/releases/mozilla-beta",
+        "repo": "https://hg.mozilla.org/releases/mozilla-release",
         "revision": "default",
-        "dest": "mozilla-beta",
+        "dest": "mozilla-release",
     }, {
         "vcs": "hgtool",
         "repo": "https://hg.mozilla.org/build/compare-locales",
         "revision": "RELEASE_AUTOMATION"
     }],
     # purge options
     'purge_minsize': 12,
     'is_automation': True,