diff --git a/.github/workflows/container_app_push.yml b/.github/workflows/container_app_push.yml
index da9cbc17f1d..8d56165db11 100644
--- a/.github/workflows/container_app_push.yml
+++ b/.github/workflows/container_app_push.yml
@@ -6,10 +6,11 @@ on:
     # Instead, push events will trigger from the base image and maven unit tests via workflow_call.
     workflow_call:
         inputs:
-            branch:
+            base-image-ref:
                 type: string
-                description: "A tag or branch to checkout for building the image"
-                required: true
+                description: "Reference of the base image to build on in full qualified form [<registry>/]<namespace>/<repo>:<tag>"
+                required: false
+                default: "gdcc/base:unstable"
     pull_request:
         branches:
             - develop
@@ -21,7 +22,6 @@ on:
 
 env:
     IMAGE_TAG: unstable
-    BASE_IMAGE_TAG: unstable
     REGISTRY: "" # Empty means default to Docker Hub
     PLATFORMS: "linux/amd64,linux/arm64"
     MASTER_BRANCH_TAG: alpha
@@ -52,6 +52,7 @@ jobs:
               run: >
                   mvn -B -f modules/dataverse-parent
                   -P ct -pl edu.harvard.iq:dataverse -am
+                  -Dbase.image.tag=${{ inputs.base-image-ref }}
                   install
 
             # TODO: add smoke / integration testing here (add "-Pct -DskipIntegrationTests=false")