diff --git a/playbooks/devstack/functional/run.yaml b/playbooks/devstack/functional/run.yaml
index 80648ddab3..7026c6947d 100644
--- a/playbooks/devstack/functional/run.yaml
+++ b/playbooks/devstack/functional/run.yaml
@@ -84,6 +84,7 @@
 
           export OVERRIDE_ENABLED_SERVICES=$services
 
+          export BRANCH_OVERRIDE="{{ branch_override | default('default') }}"
           if [ "{{ branch_override }}" != "default" ] ; then
               export OVERRIDE_ZUUL_BRANCH=$BRANCH_OVERRIDE
           fi