diff --git a/lib/util/git/index.ts b/lib/util/git/index.ts
index c9130d17189973dc4e4167340665bb966b14fda9..f714ff9149d50ab291213468095c3c7560d45838 100644
--- a/lib/util/git/index.ts
+++ b/lib/util/git/index.ts
@@ -556,6 +556,7 @@ export async function isBranchModified(branchName: string): Promise<boolean> {
     config.ignoredAuthors.some((ignoredAuthor) => lastAuthor === ignoredAuthor)
   ) {
     // author matches - branch has not been modified
+    logger.debug({ branchName }, 'Branch has not been modified');
     config.branchIsModified[branchName] = false;
     return false;
   }
diff --git a/lib/workers/branch/reuse.ts b/lib/workers/branch/reuse.ts
index a114fd864fa7d7ab0fe20daa1ff089597758f6db..00a9a062be7ca2effad4ac5f019db2cca97da788 100644
--- a/lib/workers/branch/reuse.ts
+++ b/lib/workers/branch/reuse.ts
@@ -60,6 +60,7 @@ export async function shouldReuseExistingBranch(
         logger.debug('Cannot rebase branch as it has been modified');
         return { reuseExistingBranch: true, isModified: true };
       }
+      logger.debug('Branch is unmodified, so can be rebased');
       return { reuseExistingBranch: false };
     }
     logger.debug('Branch is up-to-date');