diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 0bbdc16..3772e16 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -3,7 +3,7 @@ on:
   pull_request:
 
 jobs:
-    shopware-version:
+    shopware-version-fallback:
         runs-on: ubuntu-latest
         steps:
             - name: Checkout code
@@ -20,7 +20,68 @@ jobs:
                     echo 'shopware-version should not be empty'
                     exit 1
                 fi
-
-                
-
-
+    shopware-version:
+        runs-on: ubuntu-latest
+        strategy:
+            matrix:
+                test-case:
+                    - ref: this-branch-does-not-exist
+                      base-ref: "6.7.3.99"
+                      expected-version: "6.7.3.x"
+                    - ref: this-branch-does-not-exist
+                      base-ref: "6.6.99.99"
+                      expected-version: "6.6.x"
+                    - ref: trunk
+                      base-ref: "6.7.99.99"
+                      expected-version: "trunk"
+                    - ref: does-not-exist
+                      head-ref: trunk
+                      base-ref: "6.7.99.99"
+                      expected-version: "trunk"
+                    # for non pr events, base-ref can be empty
+                    - ref: 6.7.2.99
+                      base-ref: " "
+                      expected-version: "6.7.2.x"
+        steps:
+            - name: Checkout code
+              uses: actions/checkout@v4
+            - name: Test shopware-version
+              id: version
+              uses: ./shopware-version
+              with:
+                ref: ${{ matrix.test-case.ref }}
+                base-ref: ${{ matrix.test-case.base-ref }}
+                head-ref: ${{ matrix.test-case.head-ref || matrix.test-case.ref }}
+                repo: shopware/shopware
+                fallback: 'not-found'
+            - name: Check shopware-version matches expected version
+              run: |
+                SHOPWARE_VERSION="${{ steps.version.outputs.shopware-version }}"
+                EXPECTED_VERSION="${{ matrix.test-case.expected-version }}"
+                echo "shopware-version: '${SHOPWARE_VERSION}'"
+                echo "expected-version: '${EXPECTED_VERSION}'"
+                if [[ "${SHOPWARE_VERSION}" != "${EXPECTED_VERSION}" ]]; then
+                    echo "shopware-version should be '${EXPECTED_VERSION}' but got '${SHOPWARE_VERSION}'"
+                    exit 1
+                fi
+            - name: Test shopware-version with refs/heads/
+              id: version-heads
+              uses: ./shopware-version
+              if: ${{ matrix.test-case.base-ref != ' ' }}
+              with:
+                ref: refs/heads/${{ matrix.test-case.ref }}
+                base-ref: refs/heads/${{ matrix.test-case.base-ref }}
+                head-ref: refs/heads/${{ matrix.test-case.head-ref || matrix.test-case.ref }}
+                repo: shopware/shopware
+                fallback: 'not-found'
+            - name: Check shopware-version matches expected version
+              if: ${{ matrix.test-case.base-ref != ' ' }}
+              run: |
+                SHOPWARE_VERSION="${{ steps.version-heads.outputs.shopware-version }}"
+                EXPECTED_VERSION="${{ matrix.test-case.expected-version }}"
+                echo "shopware-version: '${SHOPWARE_VERSION}'"
+                echo "expected-version: '${EXPECTED_VERSION}'"
+                if [[ "${SHOPWARE_VERSION}" != "${EXPECTED_VERSION}" ]]; then
+                    echo "shopware-version should be '${EXPECTED_VERSION}' but got '${SHOPWARE_VERSION}'"
+                    exit 1
+                fi
\ No newline at end of file
diff --git a/setup-extension/action.yml b/setup-extension/action.yml
index fb63e6b..713ca47 100644
--- a/setup-extension/action.yml
+++ b/setup-extension/action.yml
@@ -190,7 +190,7 @@ runs:
       if: inputs.dependencies
       env:
         DEPS: ${{ inputs.dependencies }}
-        REF: ${{ inputs.shopwareVersion}}
+        REF: ${{ inputs.shopwareVersion }}
         FALLBACK: ${{ inputs.shopwareVersionFallback }}
       run: |
         for dep in $(echo "$DEPS" | envsubst | jq -c '.[]'); do
diff --git a/shopware-version/action.yml b/shopware-version/action.yml
index 01d0d4b..9c59db1 100644
--- a/shopware-version/action.yml
+++ b/shopware-version/action.yml
@@ -14,6 +14,18 @@ inputs:
     description: The repo where to look for matching refs
     default: shopware/shopware
     required: false
+  ref:
+    description: The git reference to match (defaults to github.ref)
+    required: false
+    default: ""
+  base-ref:
+    description: The base reference for pull requests (defaults to github.base_ref)
+    required: false
+    default: ""
+  head-ref:
+    description: The head reference for pull requests (defaults to github.head_ref)
+    required: false
+    default: ""
   shopware-github-token:
     description: Token used for checking out the shopware repository
     required: false
@@ -36,9 +48,9 @@ runs:
       id: get-version
       shell: bash
       env:
-        REF: "${{ github.ref }}"
-        BASE_REF: "${{ github.base_ref }}"
-        HEAD_REF: "${{ github.head_ref }}"
+        REF: "${{ inputs.ref || github.ref }}"
+        HEAD_REF: "${{ inputs.head-ref || github.head_ref }}"
+        BASE_REF: "${{ inputs.base-ref || github.base_ref }}"
         REPO: "${{ inputs.repo || 'shopware/shopware' }}"
         CURRENT_REPO: "${{ github.repository }}"
         FALLBACK: "${{ inputs.fallback || 'trunk' }}"
diff --git a/shopware-version/shopware-version.bash b/shopware-version/shopware-version.bash
index 978bd04..f933035 100755
--- a/shopware-version/shopware-version.bash
+++ b/shopware-version/shopware-version.bash
@@ -1,47 +1,117 @@
 #!/usr/bin/bash
 
+# Global environment variables required:
+# REF - The current git reference (e.g., refs/heads/6.4.1.0)
+# BASE_REF - The base reference for pull requests (e.g., 6.4.1.0)
+# HEAD_REF - The head reference for pull requests (optional)
+# REPO - The target repository to search for matching branches (e.g., shopware/shopware or https://github.com/shopware/shopware)
+# CURRENT_REPO - The current repository (e.g., shopware/platform)
+# FALLBACK - The fallback branch to use if no matching branch is found (default: trunk)
+
 set -e
 set pipefail
 
 get_ref() {
     local ref
 
+    PR_NR=$(echo "${REF}" | sed -E -n "s|^refs/heads/gh-readonly-queue/[^/]+/pr-([0-9]+)-.*$|\1|p")
+    if [[ -n "${PR_NR}" ]]; then
+        echo "refs/heads/$(gh pr view --repo "${CURRENT_REPO}" "${PR_NR}"  --jq '.headRefName' --json headRefName)"
+    fi
+
+    #remove whitespace from HEAD_REF with bash substitution
+    HEAD_REF=${HEAD_REF// /}
     if [[ -n "${HEAD_REF}" ]]; then
-        echo "refs/heads/${HEAD_REF}"
+        echo "refs/heads/${HEAD_REF#"refs/heads/"}"
     else
-        echo "${REF}"
+        #remove whitespace from REF with bash substitution
+        REF=${REF// /}
+        echo "refs/heads/${REF#"refs/heads/"}"
     fi
-
 }
 
-ref="$(get_ref)"
-echo "Local ref: ${ref}"
+get_base_ref() {
+    PR_NR=$(echo "${1}" | sed -E -n "s|^refs/heads/gh-readonly-queue/[^/]+/pr-([0-9]+)-.*$|\1|p")
+    if [[ -n "${PR_NR}" ]]; then
+        echo "$(gh pr view --repo "${CURRENT_REPO}" "${PR_NR}"  --jq '.baseRefName' --json baseRefName)"
+    fi
 
-PR_NR=$(echo "${ref}" | sed -E -n "s|^refs/heads/gh-readonly-queue/[^/]+/pr-([0-9]+)-.*$|\1|p")
-if [[ -n "${PR_NR}" ]]; then
-    echo "Found merge queue ref with PR Nr. ${PR_NR}" 2>&1
+    #remove whitespace from BASE_REF with bash substitution
+    BASE_REF=${BASE_REF// /}
+    if [[ -n "${BASE_REF}" ]]; then
+        echo "refs/heads/${BASE_REF#"refs/heads/"}"
+    fi
+}
 
-    ref="refs/heads/$(gh pr view --repo "${CURRENT_REPO}" "${PR_NR}"  --jq '.headRefName' --json headRefName)"
-    BASE_REF="$(gh pr view --repo "${CURRENT_REPO}" "${PR_NR}"  --jq '.baseRefName' --json baseRefName)"
-fi
+REF="$(get_ref)"
+echo "ref: ${REF}"
+BASE_REF="$(get_base_ref "${REF}")"
+echo "base ref: ${BASE_REF}"
 
 # if REPO does not start with https add https://github.com/
 if [[ "${REPO}" != https://* ]]; then
     REPO="https://github.com/${REPO}"
 fi
 
-remote_ref=$(git ls-remote --heads "${REPO}" "${ref}" | cut -f 2)
+# Algo for finding the matching branch in another repo
+# 1. if REF exists in target repo, use it
+# 2. if BASE_REF exists in target repo, use it
+# 3. if the next minor branch of BASE_REF exists in target repo, use it
+# 4. if the next major branch of BASE_REF exists in target repo, use it
+# 5. use fallback
+
+# to get the next minor from a patch branch replace last part with x
+# to get the next major from a patch branch replace last two parts with x
+
+
+echo "Step 1: Checking if REF '${REF}' exists in target repo '${REPO}'"
+remote_ref=$(git ls-remote --heads "${REPO}" "${REF}" | cut -f 2)
 if [[ -n "${remote_ref}" ]]; then
     version="${remote_ref#"refs/heads/"}"
+    echo "✓ Found matching REF: ${version}"
 else
-    remote_ref=$(git ls-remote --heads "${REPO}" "refs/heads/${BASE_REF}" | cut -f 2)
+    BASE_REF=${BASE_REF// /}
+    if [[ -z "${BASE_REF}" ]]; then
+        echo "✗ BASE_REF not set, using REF '${REF}'"
+        BASE_REF="${REF}"
+    fi
+
+    echo "✗ REF not found, checking BASE_REF '${BASE_REF}'"
+    # Check if BASE_REF exists in target repo
+    remote_ref=$(git ls-remote --heads "${REPO}" "${BASE_REF}" | cut -f 2)
     if [[ -n "${remote_ref}" ]]; then
         version="${remote_ref#"refs/heads/"}"
+        echo "✓ Found matching BASE_REF: ${version}"
+    else
+        echo "✗ BASE_REF not found, checking next minor branch"
+        # Check next minor branch (replace last digit with x)
+        next_minor=$(echo "${BASE_REF}" | sed -E 's/[0-9]+$/x/')
+        echo "  Checking next minor: ${next_minor}"
+        remote_ref=$(git ls-remote --heads "${REPO}" "${next_minor}" | cut -f 2)
+        if [[ -n "${remote_ref}" ]]; then
+            version="${remote_ref#"refs/heads/"}"
+            echo "✓ Found matching next minor: ${version}"
+        else
+            echo "✗ Next minor not found, checking next major branch"
+            # Check next major branch (replace last two digits with x)
+            next_major=$(echo "${BASE_REF}" | sed -E 's/[0-9]+\.[0-9]+$/x/')
+            echo "  Checking next major: ${next_major}"
+            remote_ref=$(git ls-remote --heads "${REPO}" "${next_major}" | cut -f 2)
+
+            if [[ -n "${remote_ref}" ]]; then
+                version="${remote_ref#"refs/heads/"}"
+                echo "✓ Found matching next major: ${version}"
+            else
+                echo "✗ No matching branch found, using fallback: ${FALLBACK}"
+                # Use fallback
+                version="${FALLBACK}"
+            fi
+        fi
     fi
 fi
 
 if [[ -z "$version" ]]; then
-    echo "$ref not found in ${REPO}, using fallback "
+    echo "$REF not found in ${REPO}, using fallback "
     version="${FALLBACK}"
 fi