--- a/process/release.py
+++ b/process/release.py
@@ -1776,17 +1776,18 @@ def generateReleasePromotionBuilders(bra
         balrog_config = "balrog/production.py"
         if branch_config.get("staging"):
             env_config = "single_locale/staging.py"
             balrog_config = "balrog/staging.py"
 
         mh_cfg = {
             "script_name": "scripts/desktop_l10n.py",
             "extra_args": [
-                "--branch-config", "single_locale/%s.py" % branch_name,
+                "--branch-config", "single_locale/%s.py" % branch_config.get('single_locale_branch_config',
+                                                                             branch_name),
                 "--platform-config", "single_locale/%s.py" % platform,
                 "--environment-config", env_config,
                 "--balrog-config", balrog_config,
                                    ],
             "script_timeout": 1800,
             "script_maxtime": 7200,
         }