try putting IMAGE_TAG at top level

.github/workflows/build-publish-ondemand.yml

@@ -15,6 +15,9 @@ on:
     paths:
       - 'ondemand/**'
 
+env:
+  IMAGE_TAG: $(date +"%Y%m%d")
+
 jobs:
   build_publish_ondemand:
     name: Build/publish ondemand container
@@ -32,12 +35,6 @@ jobs:
         run: |
           echo PUBLISH_IMAGES=1 >> $GITHUB_ENV
 
-      - name: Set a tag based on the date
-        run: |
-          IMAGE_TAG=$(date +"%Y%m%d")
-          echo IMAGE_TAG=$IMAGE_TAG >> $GITHUB_ENV
-          echo "Image tag is $IMAGE_TAG"
-
       - name: Determine latest release of ondemand
         id: getlatestrelease
         run: |