diff --git a/release-mcp-version.groovy b/release-mcp-version.groovy
index 7c30f30..744936f 100644
--- a/release-mcp-version.groovy
+++ b/release-mcp-version.groovy
@@ -56,11 +56,12 @@
   ]
 }
 
-def triggerGitTagJob(gitRepoList, gitCredentials, tag) {
+def triggerGitTagJob(gitRepoList, gitCredentials, tag, source_tag) {
   build job: "tag-git-repos-stable", parameters: [
     [$class: 'StringParameterValue', name: 'GIT_REPO_LIST', value: gitRepoList],
     [$class: 'StringParameterValue', name: 'GIT_CREDENTIALS', value: gitCredentials],
-    [$class: 'StringParameterValue', name: 'TAG', value: tag]
+    [$class: 'StringParameterValue', name: 'TAG', value: tag],
+    [$class: 'StringParameterValue', name: 'SOURCE_TAG', value: source_tag],
   ]
 }
 
diff --git a/tag-git-repos.groovy b/tag-git-repos.groovy
index 52344d1..bb3f7a5 100644
--- a/tag-git-repos.groovy
+++ b/tag-git-repos.groovy
@@ -6,6 +6,7 @@
  *   GIT_REPO_LIST
  *   GIT_CREDENTIALS
  *   TAG
+ *   SOURCE_TAG initial commit\tag to be tagged with TAG
  *
  */
 
@@ -35,6 +36,11 @@
                 repoName = repoArray[0]
                 repoUrl = repoArray[1]
                 repoCommit = repoArray[2]
+                if (repoCommit.contains('SUBS_SOURCE_REF')) {
+                    common.warningMsg("Replacing SUBS_SOURCE_REF => ${SOURCE_TAG}")
+                    repoCommit.replace('SUBS_SOURCE_REF', SOURCE_TAG
+                        )
+                }
                 gitRepoAddTag(repoUrl, repoName, TAG, GIT_CREDENTIALS, repoCommit)
             }
         } catch (Throwable e) {