diff --git a/.github/workflows/mantle-releases-main.yml b/.github/workflows/mantle-releases-main.yml
new file mode 100644
index 0000000000..7942f713f3
--- /dev/null
+++ b/.github/workflows/mantle-releases-main.yml
@@ -0,0 +1,54 @@
+name: Get the latest mantle release for branch
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - main
+  schedule:
+    - cron:  '0 7 * * 1'
+
+jobs:
+  get-mantle-release:
+    strategy:
+      matrix:
+        branch: [main,alpha,beta,stable]
+      fail-fast: false
+    runs-on: ubuntu-latest
+    steps:
+      - name: Figure out branch
+        id: figure-out-branch
+        run: |
+          if [ ${{ matrix.branch }} = "main" ]; then
+            echo ::set-output name=BRANCH::main
+          else
+            major=$(curl -sSL https://${{ matrix.branch }}.release.flatcar-linux.net/amd64-usr/current/version.txt | awk -F= '/FLATCAR_BUILD=/{ print $2 }')
+            echo ::set-output name=BRANCH::flatcar-${major}
+          fi
+      - uses: actions/checkout@v2
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          ref: ${{ steps.figure-out-branch.outputs.BRANCH }}
+      - name: Fetch latest mantle hash
+        id: fetch-latest-mantle
+        run: |
+          commit=$(git ls-remote  https://github.com/flatcar-linux/mantle refs/heads/flatcar-master | cut -f1)
+          echo ::set-output name=COMMIT::${commit}
+      - name: Try to apply patch
+        run: |
+          set -x
+          commit=${{ steps.fetch-latest-mantle.outputs.COMMIT }}
+          if ! grep -q "ghcr.io/flatcar-linux/mantle:git-${commit}" sdk_container/.repo/manifests/mantle-container; then
+            echo "ghcr.io/flatcar-linux/mantle:git-${commit}" > sdk_container/.repo/manifests/mantle-container
+            git add sdk_container/.repo/manifests/mantle-container
+          fi
+      - name: Create pull request for branch
+        uses: peter-evans/create-pull-request@v3
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          base: ${{ steps.figure-out-branch.outputs.BRANCH }}
+          branch: mantle-update-${{ steps.figure-out-branch.outputs.BRANCH }}
+          author: Flatcar Buildbot <buildbot@flatcar-linux.org>
+          committer: Flatcar Buildbot <buildbot@flatcar-linux.org>
+          title: Upgrade mantle container image to latest HEAD in ${{ steps.figure-out-branch.outputs.BRANCH }}
+          commit-message: Update mantle container image to latest HEAD
+          delete-branch: true
diff --git a/ci-automation/test.sh b/ci-automation/test.sh
index 8e9246f2cf..c660bd8f9c 100644
--- a/ci-automation/test.sh
+++ b/ci-automation/test.sh
@@ -118,35 +118,23 @@ function test_run() {
     local docker_vernum
     docker_vernum="$(vernum_to_docker_image_version "${vernum}")"
 
-    # Get SDK from either the registry or import from build cache
-    local sdk_version="${FLATCAR_SDK_VERSION}"
-    local sdk_name="flatcar-sdk-${arch}"
-    local docker_sdk_vernum="$(vernum_to_docker_image_version "${sdk_version}")"
-
-    docker_image_from_registry_or_buildcache "${sdk_name}" "${docker_sdk_vernum}"
-    local sdk_image="$(docker_image_fullname "${sdk_name}" "${docker_sdk_vernum}")"
-    echo "docker image rm -f '${sdk_image}'" >> ./ci-cleanup.sh
-
     local work_dir="__TESTS__"
     local tests_dir="${work_dir}/${image}"
     mkdir -p "${tests_dir}"
 
     local container_name="flatcar-tests-${arch}-${docker_vernum}-${image}"
+    local mantle_ref
+    mantle_ref=$(cat sdk_container/.repo/manifests/mantle-container)
 
     # Make the torcx artifacts available to test implementation
     __prepare_torcx "${arch}" "${vernum}" "${work_dir}"
 
-    # Ensure we run tests with an up-to-date kola.
-    # This covers the case of a mantle/kola commit ID in the ebuild being
-    #  newer than the mantle/kola included in the SDK.
-    ./run_sdk_container -x ./ci-cleanup.sh \
-        -n "${container_name}" -C "${sdk_image}" -v "${vernum}" \
-        sudo emerge mantle
-
     local tap_merged_summary="results-${image}.tap"
     local tap_merged_detailed="results-${image}-detailed.tap"
     local retry=""
     local success=false
+    # A job on each worker prunes old mantle images (docker image prune)
+    echo "docker rm -f '${container_name}'" >> ./ci-cleanup.sh
     for retry in $(seq "${retries}"); do
         local tapfile="results-run-${retry}.tap"
         local failfile="failed-run-${retry}.txt"
@@ -154,18 +142,19 @@ function test_run() {
         # Ignore retcode since tests are flaky. We'll re-run failed tests and
         #  determine success based on test results (tapfile).
         set +e -o noglob
-        ./run_sdk_container -x ./ci-cleanup.sh \
-            -n "${container_name}" -C "${sdk_image}" -v "${vernum}" \
-            ci-automation/vendor-testing/"${image}".sh \
-                "${tests_dir}" \
-                "${arch}" \
-                "${vernum}" \
-                "${tapfile}" \
-                $@
+        touch sdk_container/.env
+        docker run --pull always --rm --name="${container_name}" --privileged --net host -v /dev:/dev \
+          -w /work -v "$PWD":/work "${mantle_ref}" \
+         bash -c "set -o noglob && source sdk_container/.env && ci-automation/vendor-testing/\"${image}\".sh \
+                \"${tests_dir}\" \
+                \"${arch}\" \
+                \"${vernum}\" \
+                \"${tapfile}\" \
+                $@"
         set -e +o noglob
 
-        ./run_sdk_container -x ./ci-cleanup.sh \
-            -n "${container_name}" -C "${sdk_image}" -v "${vernum}" \
+        docker run --pull always --rm --name="${container_name}" --privileged --net host -v /dev:/dev \
+          -w /work -v "$PWD":/work "${mantle_ref}" \
             ci-automation/test_update_reruns.sh \
                 "${arch}" "${vernum}" "${image}" "${retry}" \
                 "${tests_dir}/${tapfile}" \
diff --git a/sdk_container/.repo/manifests/mantle-container b/sdk_container/.repo/manifests/mantle-container
new file mode 100644
index 0000000000..5a95770c74
--- /dev/null
+++ b/sdk_container/.repo/manifests/mantle-container
@@ -0,0 +1 @@
+ghcr.io/flatcar-linux/mantle:git-cdf70a21b356e6ed6b1da0cb2bf57deeea8e48f7