diff --git a/.github/workflows/integration-test.yml b/.github/workflows/integration-test.yml
index b0d1c53..ac3bdfa 100644
--- a/.github/workflows/integration-test.yml
+++ b/.github/workflows/integration-test.yml
@@ -131,8 +131,8 @@ jobs:
           name: junit-xml-reports-${{ matrix.split-index }}
           path: build/reports/test-results/*.xml
 
-  merge-junit-reports:
-    name: Merge JUnit reports
+  merge-junit-reports-with-existing-branch:
+    name: Merge JUnit reports with existing branch
     runs-on: ubuntu-latest
     needs:
       - integration-test
@@ -142,18 +142,84 @@ jobs:
       - name: Checkout split-tests-java-action
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
 
+      - name: Create JUnit reports branch
+        run: |
+          BRANCH=junit-reports-it-${{ github.sha }}-existing
+          echo "Creating branch $BRANCH"
+          git switch --orphan $BRANCH
+          git config user.name "${{ github.actor }}"
+          git config user.email "${{ github.actor }}@users.noreply.github.com"
+          git commit --allow-empty -m "Initial commit for JUnit reports branch"
+          git push origin --set-upstream $BRANCH
+          git switch ${{ github.ref_name }}
+
+      - name: Merge JUnit reports
+        uses: ./merge-junit-reports
+        with:
+          git-branch: junit-reports-it-${{ github.sha }}-existing
+          artifact-name: junit-xml-report-existing
+          split-artifact-pattern: junit-xml-reports-*
+          split-artifact-delete-merged: false
+
+      - name: Checkout JUnit reports
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+        with:
+          path: junit-reports-assertion
+          ref: junit-reports-it-${{ github.sha }}-existing
+
+      - name: Assert JUnit reports
+        working-directory: junit-reports-assertion
+        run: |
+          for SPLIT_INDEX in {0..3}; do
+            REPORT_FILE="TEST-de.donnerbart.example.ActionSplit${SPLIT_INDEX}Test.xml"
+            SEARCH_STRING='name="de.donnerbart.example.ActionSplit'${SPLIT_INDEX}'Test"'
+            if [[ ! -f "$REPORT_FILE" ]]; then
+              echo "Error: JUnit report $REPORT_FILE not found!"
+              ls -l
+              exit 1
+            fi
+            if ! grep -q "$SEARCH_STRING" "$REPORT_FILE"; then
+              echo "Error: JUnit report $REPORT_FILE does not contain the required string '$SEARCH_STRING'!"
+              cat $REPORT_FILE
+              exit 1
+            fi
+            echo "JUnit report $REPORT_FILE is valid"
+          done
+          FILE_COUNT=$(ls -1 | wc -l)
+          if [[ "$FILE_COUNT" -ne 4 ]]; then
+            echo "Error: Expected 4 JUnit reports, but found $FILE_COUNT files!"
+            ls -l
+            exit 1
+          fi
+
+      - name: Cleanup JUnit reports branch
+        if: always()
+        run: |
+          git push origin --delete junit-reports-it-${{ github.sha }}-existing || true
+
+  merge-junit-reports-with-new-branch:
+    name: Merge JUnit reports with new branch
+    runs-on: ubuntu-latest
+    needs:
+      - merge-junit-reports-with-existing-branch
+    permissions:
+      contents: write
+    steps:
+      - name: Checkout split-tests-java-action
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+
       - name: Merge JUnit reports
         uses: ./merge-junit-reports
         with:
-          git-branch: junit-reports-it-${{ github.sha }}
-          artifact-name: junit-xml-reports
+          git-branch: junit-reports-it-${{ github.sha }}-new
+          artifact-name: junit-xml-report-new
           split-artifact-pattern: junit-xml-reports-*
 
       - name: Checkout JUnit reports
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
         with:
           path: junit-reports-assertion
-          ref: junit-reports-it-${{ github.sha }}
+          ref: junit-reports-it-${{ github.sha }}-new
 
       - name: Assert JUnit reports
         working-directory: junit-reports-assertion
@@ -183,7 +249,7 @@ jobs:
       - name: Download JUnit reports artifact
         uses: actions/download-artifact@cc203385981b70ca67e1cc392babf9cc229d5806 # v4
         with:
-          name: junit-xml-reports
+          name: junit-xml-report-new
           path: junit-reports-artifact-assertion
 
       - name: Assert JUnit reports artifact
@@ -214,4 +280,4 @@ jobs:
       - name: Cleanup JUnit reports branch
         if: always()
         run: |
-          git push origin --delete junit-reports-it-${{ github.sha }} || true
+          git push origin --delete junit-reports-it-${{ github.sha }}-new || true
diff --git a/merge-junit-reports/action.yml b/merge-junit-reports/action.yml
index 943d6ba..83861c7 100644
--- a/merge-junit-reports/action.yml
+++ b/merge-junit-reports/action.yml
@@ -45,11 +45,11 @@ runs:
       working-directory: junit-reports
       run: |
         if git ls-remote --exit-code --heads origin ${{ inputs.git-branch }}; then
-          echo "Switching to branch ${{ inputs.git-branch }}"
+          echo "Switching to existing branch ${{ inputs.git-branch }}"
           git fetch --quiet
           git switch ${{ inputs.git-branch }}
         else
-          echo "Creating branch ${{ inputs.git-branch }}"
+          echo "Creating new branch ${{ inputs.git-branch }}"
           git switch --orphan ${{ inputs.git-branch }}
           git config user.name "${{ github.actor }}"
           git config user.email "${{ github.actor }}@users.noreply.github.com"