diff --git a/lib/workers/branch/auto-replace.ts b/lib/workers/branch/auto-replace.ts
index e39704a96d5c02b22b4f0eab27237a0c8adbc699..710ec4b2e40ee400a0f4498c474c203f9365ae16 100644
--- a/lib/workers/branch/auto-replace.ts
+++ b/lib/workers/branch/auto-replace.ts
@@ -83,7 +83,7 @@ export async function doAutoReplace(
     newDigest,
     autoReplaceData,
   } = upgrade;
-  const { replaceString } = autoReplaceData;
+  const replaceString = autoReplaceData.replaceString || currentValue;
   try {
     let newString = replaceString;
     do {