diff --git a/.github/workflows/docker.yml b/.github/workflows/docker.yml
index 2adceaa4d3c3..dd44e92f0470 100644
--- a/.github/workflows/docker.yml
+++ b/.github/workflows/docker.yml
@@ -121,6 +121,10 @@ jobs:
     secrets:
       DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
       DOCKER_ACCESS_TOKEN: ${{ secrets.DOCKER_ACCESS_TOKEN }}
+      # Enable redeploy of sandbox & demo SOLR instance whenever dspace-solr image changes for deployed branch.
+      # These URLs MUST use different secrets than 'dspace/dspace' image build above as they are deployed separately.
+      REDEPLOY_SANDBOX_URL: ${{ secrets.REDEPLOY_SANDBOX_SOLR_URL }}
+      REDEPLOY_DEMO_URL: ${{ secrets.REDEPLOY_DEMO_SOLR_URL }}
 
   ###########################################################
   # Build/Push the 'dspace/dspace-postgres-pgcrypto' image