diff --git a/.github/workflows/frontend_charm_analysis.yml b/.github/workflows/frontend_charm_analysis.yml
index 751c14bef..707d6b287 100644
--- a/.github/workflows/frontend_charm_analysis.yml
+++ b/.github/workflows/frontend_charm_analysis.yml
@@ -4,13 +4,13 @@ on:
     branches:
       - main
   push:
-    branches: ["main"]
+    branches: ["main", "integration-test-fix"]
     tags: ["v*.*.*"]
 
 jobs:
   lint-report:
     name: Lint and format report
-    runs-on: ubuntu-22.04
+    runs-on: [self-hosted, linux, large]
     steps:
       - uses: actions/checkout@v3
       - name: Install tox
@@ -23,7 +23,7 @@ jobs:
 
   static-analysis:
     name: Static analysis
-    runs-on: ubuntu-22.04
+    runs-on: [self-hosted, linux]
     steps:
       - uses: actions/checkout@v3
       - name: Install tox
@@ -36,7 +36,7 @@ jobs:
 
   unit-tests-with-coverage:
     name: Unit tests
-    runs-on: ubuntu-22.04
+    runs-on: [self-hosted, linux]
     steps:
       - uses: actions/checkout@v3
       - name: Install tox
diff --git a/.github/workflows/frontend_charm_integration_tests.yml b/.github/workflows/frontend_charm_integration_tests.yml
index 80670c320..18ad95f6e 100644
--- a/.github/workflows/frontend_charm_integration_tests.yml
+++ b/.github/workflows/frontend_charm_integration_tests.yml
@@ -1,13 +1,17 @@
 name: Run charm tests
 on:
   push:
-    branches: ["main"]
+    branches: ["main", "integration-test-fix"]
     tags: ["v*.*.*"]
 
 jobs:
   integration-test:
+    permissions:
+      contents: read
+      packages: read
+
     name: Integration tests
-    runs-on: ubuntu-22.04
+    runs-on: [self-hosted, linux, large]
     steps:
       - name: Checkout
         uses: actions/checkout@v3
@@ -16,9 +20,32 @@ jobs:
         with:
           channel: 5.13/stable
       - name: Setup operator environment
-        uses: charmed-kubernetes/actions-operator@main
+        uses: charmed-kubernetes/actions-operator@main # mz2/actions-operator@4fcb55b99e2a0f69a5910870d3639d203aeb87aa
         with:
+          channel: 1.27/stable # 1.26.4
           provider: microk8s
+          juju-channel: 3.0/stable
+          # juju-classic-confinement: "false"
+          # microk8s-classic-confinement: "false"
+          charmcraft-channel: 2.x/stable
+          lxd-channel: 5.13/stable
+      - name: Adjust containerd template to accept ghcr.io images
+        run: |
+          sudo mkdir -p /var/snap/microk8s/current/args &&
+          echo "" | sudo tee -a /var/snap/microk8s/current/args/containerd-template.toml &&
+          echo '[plugins."io.containerd.grpc.v1.cri".registry.configs."ghcr.io".auth]' | sudo tee -a /var/snap/microk8s/current/args/containerd-template.toml &&
+          echo '  username = "$GHCR_PACKAGE_API_USER"' | sudo tee -a /var/snap/microk8s/current/args/containerd-template.toml &&
+          echo '  password = "$GHCR_PACKAGE_API_TOKEN"' | sudo tee -a /var/snap/microk8s/current/args/containerd-template.toml &&
+          sudo systemctl restart snap.microk8s.daemon-containerd.service && 
+          sudo microk8s.stop &&
+          sleep 10 &&
+          sudo microk8s.start &&
+          sleep 10 &&
+          sudo microk8s status --wait-ready &&
+          sleep 30
+        env:
+          GHCR_PACKAGE_API_USER: ${{ secrets.GHCR_PACKAGE_API_USER }}
+          GHCR_PACKAGE_API_TOKEN: ${{ secrets.GHCR_PACKAGE_API_TOKEN }}
       - name: Run integration tests
         run: tox -e integration
       - name: Archive Tested Charm
@@ -43,3 +70,29 @@ jobs:
     defaults:
       run:
         working-directory: ./frontend/charm
+
+  publish-charm:
+    name: Publish Charm
+    needs: integration-test
+    runs-on: [self-hosted, linux]
+    if: ${{ github.ref_name == 'main' }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Install charmcraft
+        run: sudo snap install charmcraft --classic
+      - name: Fetch Tested Charm
+        uses: actions/download-artifact@v3
+        with:
+          name: tested-charm
+      - name: Move charm in current directory
+        run: find ./ -name test-observer-frontend_ubuntu-22.04-amd64.charm -exec mv -t ./ {} \;
+      - name: Select Charmhub channel
+        uses: canonical/charming-actions/channel@2.2.2
+        id: channel
+      - name: Upload charm to Charmhub
+        uses: canonical/charming-actions/upload-charm@2.2.2
+        with:
+          credentials: "${{ secrets.CHARMHUB_AUTH_API }}"
+          github-token: "${{ secrets.GITHUB_TOKEN }}"
+          channel: "${{ steps.channel.outputs.name }}"
diff --git a/.github/workflows/frontend_charm_promote.yml b/.github/workflows/frontend_charm_promote.yml
new file mode 100644
index 000000000..a04866df9
--- /dev/null
+++ b/.github/workflows/frontend_charm_promote.yml
@@ -0,0 +1,43 @@
+name: Promote Charm
+
+on:
+  workflow_dispatch:
+    inputs:
+      promotion:
+        type: choice
+        description: Channel to promote from
+        options:
+          - edge -> beta
+          - beta -> candidate
+          - candidate -> stable
+
+jobs:
+  promote:
+    name: Promote Charm
+    runs-on: [self-hosted, linux]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Set target channel
+        env:
+          PROMOTE_FROM: ${{ github.event.inputs.promotion }}
+        run: |
+          if [ "${PROMOTE_FROM}" == "edge -> beta" ]; then
+            echo "promote-from=edge" >> ${GITHUB_ENV}
+            echo "promote-to=beta" >> ${GITHUB_ENV}
+          elif [ "${PROMOTE_FROM}" == "beta -> candidate" ]; then
+            echo "promote-from=beta" >> ${GITHUB_ENV}
+            echo "promote-to=candidate" >> ${GITHUB_ENV}
+          elif [ "${PROMOTE_FROM}" == "candidate -> stable" ]; then
+            echo "promote-from=candidate" >> ${GITHUB_ENV}
+            echo "promote-to=stable" >> ${GITHUB_ENV}
+          fi
+      - name: Promote Charm
+        uses: canonical/charming-actions/release-charm@2.2.0
+        with:
+          base-channel: 22.04
+          credentials: ${{ secrets.CHARMHUB_TOKEN }}
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          destination-channel: latest/${{ env.promote-to }}
+          origin-channel: latest/${{ env.promote-from }}
+          charmcraft-channel: latest/stable
diff --git a/.github/workflows/public_backend_image.yml b/.github/workflows/public_backend_image.yml
index 0e74e6430..5f1653a9c 100644
--- a/.github/workflows/public_backend_image.yml
+++ b/.github/workflows/public_backend_image.yml
@@ -9,7 +9,7 @@ env:
 
 jobs:
   build-and-push-backend-image:
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, linux]
     permissions:
       contents: read
       packages: write
diff --git a/.github/workflows/publish_frontend_image.yml b/.github/workflows/publish_frontend_image.yml
index 3b901b821..982edb457 100644
--- a/.github/workflows/publish_frontend_image.yml
+++ b/.github/workflows/publish_frontend_image.yml
@@ -9,7 +9,7 @@ env:
 
 jobs:
   build-and-push-frontend-image:
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, linux]
     permissions:
       contents: read
       packages: write
diff --git a/.github/workflows/release_charms.yml b/.github/workflows/release_charms.yml
index b344a8106..148b8b753 100644
--- a/.github/workflows/release_charms.yml
+++ b/.github/workflows/release_charms.yml
@@ -9,7 +9,7 @@ on:
 jobs:
   build:
     name: Release test-observer-api charm to edge
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, linux]
     steps:
       - name: Checkout
         uses: actions/checkout@v2
diff --git a/.github/workflows/test_backend.yml b/.github/workflows/test_backend.yml
index 223752b3b..a2718155a 100644
--- a/.github/workflows/test_backend.yml
+++ b/.github/workflows/test_backend.yml
@@ -6,7 +6,7 @@ concurrency:
   cancel-in-progress: true
 jobs:
   test:
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, linux, large]
     defaults:
       run:
         working-directory: backend
diff --git a/.github/workflows/test_frontend.yml b/.github/workflows/test_frontend.yml
index 5a99a692b..c2f76f534 100644
--- a/.github/workflows/test_frontend.yml
+++ b/.github/workflows/test_frontend.yml
@@ -6,7 +6,7 @@ concurrency:
   cancel-in-progress: true
 jobs:
   test:
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, linux, large]
     defaults:
       run:
         working-directory: frontend
diff --git a/frontend/charm/metadata.yaml b/frontend/charm/metadata.yaml
index 767c3d4c3..3a4857d29 100644
--- a/frontend/charm/metadata.yaml
+++ b/frontend/charm/metadata.yaml
@@ -21,4 +21,4 @@ resources:
   frontend-image:
     type: oci-image
     description: OCI image for test-observer-frontend
-    upstream-source: ghcr.io/canonical/test_observer/frontend:v0.0.10
+    upstream-source: ghcr.io/canonical/test_observer/frontend:v0.0.10
\ No newline at end of file
diff --git a/frontend/charm/src/charm.py b/frontend/charm/src/charm.py
index f85192eaf..f9f997677 100755
--- a/frontend/charm/src/charm.py
+++ b/frontend/charm/src/charm.py
@@ -15,7 +15,6 @@
     IngressPerAppRequirer,
     IngressPerAppRevokedEvent,
 )
-from ops.framework import StoredState
 from ops.model import (
     ActiveStatus,
     BlockedStatus,
@@ -30,8 +29,6 @@
 class TestObserverFrontendCharm(ops.CharmBase):
     """The frontend charm operates serving the frontend through nginx."""
 
-    _stored = StoredState()
-
     def __init__(self, *args):
         super().__init__(*args)
         self.pebble_service_name = "test-observer-frontend"
@@ -56,8 +53,6 @@ def __init__(self, *args):
         self.framework.observe(self.ingress.on.ready, self._on_ingress_ready)
         self.framework.observe(self.ingress.on.revoked, self._on_ingress_revoked)
 
-        self._stored.set_default(backend_hostname=None, backend_port=None)
-
     def _on_frontend_pebble_ready(self, event: ops.PebbleReadyEvent):
         container = event.workload
         container.add_layer("frontend", self._pebble_layer, combine=True)
@@ -98,20 +93,12 @@ def _config_is_valid(self, config) -> Tuple[bool, str]:
     def _on_rest_api_relation_update(self, event):
         api_hostname = event.relation.data[event.app].get("hostname")
         api_port = event.relation.data[event.app].get("port")
-        logger.debug(f"API hostname: {api_hostname} (app: {event.app})")
-
-        if self.unit.is_leader():
-            self._stored.backend_hostname = api_hostname
-            self._stored.backend_port = api_port
-
+        logger.debug(f"API hostname: {api_hostname}, port: {api_port} (app: {event.app})")
         self._update_layer_and_restart(event)
 
     def _on_rest_api_relation_broken(self, event):
-        logger.debug("REST API relation broken -> removing backend hostname")
-
-        if self.unit.is_leader():
-            self._stored.backend_hostname = None
-            self._stored.backend_port = None
+        logger.debug("REST API relation broken")
+        self._update_layer_and_restart(event)
 
     def nginx_config(self, base_uri: str) -> str:
         """Return a config where the backend port `base_uri` is adjusted."""
@@ -136,30 +123,91 @@ def nginx_config(self, base_uri: str) -> str:
         }}
         """
 
+    def nginx_503_config(self) -> str:
+        """Return a config for the situation when the backend is not yet available."""
+        return """
+        server {
+            listen 80 default_server;
+            server_name _;
+            return 503;
+            error_page 503 @maintenance;
+
+            location @maintenance {
+                rewrite ^(.*)$ /503.html break;
+                root /usr/share/nginx/html;
+            }
+        }
+        """
+
+    def html_503(self) -> str:
+        """Return a 503 response page."""
+        return """
+        <html>
+            <head>
+                <title>503 Service Unavailable</title>
+            </head>
+            <body>
+                <h1>503 Service Unavailable</h1>
+                <p>Backend not yet configured.</p>
+            </body>
+        </html>
+        """
+
     def _update_layer_and_restart(self, event):
         self.unit.status = MaintenanceStatus(f"Updating {self.pebble_service_name} layer")
 
+        api_relation = self.model.relations["test-observer-rest-api"][0]
+
+        if api_relation is None:
+            if self.container.can_connect():
+                self.container.add_layer(
+                    self.pebble_service_name, self._pebble_layer, combine=True
+                )
+                self.container.push(
+                    "/etc/nginx/sites-available/test-observer-frontend",
+                    self.nginx_503_config(),
+                    make_dirs=True,
+                )
+                self.container.push(
+                    "/usr/share/nginx/html/503.html",
+                    self.html_503(),
+                    make_dirs=True,
+                )
+                self.container.restart(self.pebble_service_name)
+                self.unit.status = MaintenanceStatus(
+                    "test-observer-rest-api relation not connected."
+                )
+            else:
+                self.unit.status = WaitingStatus(
+                    "Waiting for Pebble for API to set maintenance state"
+                )
+
+            return
+
+        hostname = api_relation.data[api_relation.app]["hostname"]
+        port = api_relation.data[api_relation.app]["port"]
+
         scheme = self.config["test-observer-api-scheme"]
-        hostname = self._stored.backend_hostname
-        port = self._stored.backend_port
+
+        logger.info(f"Hostname: {hostname} (from relation: {hostname})")
+        logger.info(f"Port: {port} (from relation: {port})")
 
         if int(port) == 80 or int(port) == 443:
             base_uri = f"{scheme}{hostname}"
         else:
             base_uri = f"{scheme}{hostname}:{port}"
 
-        self.container.push(
-            "/etc/nginx/sites-available/test-observer-frontend",
-            self.nginx_config(base_uri=base_uri),
-            make_dirs=True,
-        )
-
         if self.container.can_connect():
             self.container.add_layer(self.pebble_service_name, self._pebble_layer, combine=True)
+            self.container.push(
+                "/etc/nginx/sites-available/test-observer-frontend",
+                self.nginx_config(base_uri=base_uri),
+                make_dirs=True,
+            )
             self.container.restart(self.pebble_service_name)
             self.unit.status = ActiveStatus()
         else:
-            self.unit.status = WaitingStatus("Waiting for Pebble for API")
+            self.unit.status = WaitingStatus("Waiting for Pebble for API to set available state")
 
     @property
     def _pebble_layer(self):
diff --git a/frontend/charm/tests/integration/test_charm.py b/frontend/charm/tests/integration/test_charm.py
index 10742f61b..77cc33f3a 100644
--- a/frontend/charm/tests/integration/test_charm.py
+++ b/frontend/charm/tests/integration/test_charm.py
@@ -17,8 +17,8 @@
 
 
 @pytest.mark.abort_on_fail
-async def test_build_and_deploy(ops_test: OpsTest):
-    """Build the charm-under-test and deploy it together with related charms.
+async def test_build_and_deploy_without_backend(ops_test: OpsTest):
+    """Build the charm-under-test and deploy it together without related charms.
 
     Assert on the unit status before any relations/configurations take place.
     """
@@ -29,8 +29,7 @@ async def test_build_and_deploy(ops_test: OpsTest):
         ops_test.model.deploy(charm, resources=resources, application_name=APP_NAME),
         ops_test.model.wait_for_idle(
             apps=[APP_NAME],
-            status="active",
-            raise_on_blocked=True,
-            timeout=1000,
+            status="maintenance",
+            timeout=2000,
         ),
     )
diff --git a/frontend/charm/tox.ini b/frontend/charm/tox.ini
index fb9bfa4f4..d205153ad 100644
--- a/frontend/charm/tox.ini
+++ b/frontend/charm/tox.ini
@@ -66,7 +66,7 @@ commands =
 description = Run integration tests
 deps =
     pytest
-    juju
+    juju<3.1
     pytest-operator
     -r {tox_root}/requirements.txt
 commands =