diff --git a/testing/mozharness/configs/merge_day/aurora_to_beta.py b/testing/mozharness/configs/merge_day/aurora_to_beta.py
index 981fa0d09c58..6f9af566bac4 100644
--- a/testing/mozharness/configs/merge_day/aurora_to_beta.py
+++ b/testing/mozharness/configs/merge_day/aurora_to_beta.py
@@ -38,9 +38,6 @@ config = {
                   "browser/config/mozconfigs/win64/l10n-mozconfig",
                   "browser/config/mozconfigs/macosx64/l10n-mozconfig"]
     ] + [
-        ("browser/config/mozconfigs/macosx64/nightly",
-         "ac_add_options --with-branding=browser/branding/aurora",
-         "ac_add_options --with-branding=browser/branding/nightly"),
         ("browser/confvars.sh",
          "ACCEPTED_MAR_CHANNEL_IDS=firefox-mozilla-aurora",
          "ACCEPTED_MAR_CHANNEL_IDS=firefox-mozilla-beta,firefox-mozilla-release"),
diff --git a/testing/mozharness/configs/merge_day/central_to_aurora.py b/testing/mozharness/configs/merge_day/central_to_aurora.py
index 292015959766..3db1b5ced99a 100644
--- a/testing/mozharness/configs/merge_day/central_to_aurora.py
+++ b/testing/mozharness/configs/merge_day/central_to_aurora.py
@@ -52,12 +52,6 @@ config = {
         ("browser/confvars.sh",
          "MAR_CHANNEL_ID=firefox-mozilla-central",
          "MAR_CHANNEL_ID=firefox-mozilla-aurora"),
-        ("browser/config/mozconfigs/macosx64/nightly",
-         "ac_add_options --with-branding=browser/branding/nightly",
-         "ac_add_options --with-branding=browser/branding/aurora"),
-        ("browser/config/mozconfigs/macosx64/l10n-mozconfig",
-         "ac_add_options --with-branding=browser/branding/nightly",
-         "ac_add_options --with-branding=browser/branding/aurora"),
         ("browser/config/mozconfigs/whitelist",
          "ac_add_options --with-branding=browser/branding/nightly",
          "ac_add_options --with-branding=browser/branding/aurora"),