diff --git a/devstack-vm-gate-wrap.sh b/devstack-vm-gate-wrap.sh
index 2e58299f..2720b34e 100755
--- a/devstack-vm-gate-wrap.sh
+++ b/devstack-vm-gate-wrap.sh
@@ -267,6 +267,9 @@ if [[ -n "$DEVSTACK_GATE_GRENADE" ]]; then
                 export GRENADE_NEW_BRANCH="stable/kilo"
             elif [[ "$GRENADE_BASE_BRANCH" == "stable/kilo" ]]; then
                 export GRENADE_OLD_BRANCH="stable/kilo"
+                export GRENADE_NEW_BRANCH="stable/liberty"
+            elif [[ "$GRENADE_BASE_BRANCH" == "stable/liberty" ]]; then
+                export GRENADE_OLD_BRANCH="stable/liberty"
                 export GRENADE_NEW_BRANCH="$GIT_BRANCH"
             fi
             ;;
@@ -291,8 +294,16 @@ if [[ -n "$DEVSTACK_GATE_GRENADE" ]]; then
             elif [[ "$GRENADE_BASE_BRANCH" == "stable/kilo" ]]; then
                 export GRENADE_OLD_BRANCH="stable/juno"
                 export GRENADE_NEW_BRANCH="stable/kilo"
-            else # master
+            elif [[ "$GRENADE_BASE_BRANCH" == "stable/liberty" ]]; then
                 export GRENADE_OLD_BRANCH="stable/kilo"
+                export GRENADE_NEW_BRANCH="stable/liberty"
+            elif [[ "$GRENADE_BASE_BRANCH" == "stable/mitaka" ]]; then
+                # not used yet, but will be used when we cut the
+                # stable mitaka branch
+                export GRENADE_OLD_BRANCH="stable/liberty"
+                export GRENADE_NEW_BRANCH="stable/mitaka"
+            else # master
+                export GRENADE_OLD_BRANCH="stable/liberty"
                 export GRENADE_NEW_BRANCH="$GIT_BRANCH"
             fi
             ;;