diff --git a/reference/legacy.yaml b/reference/legacy.yaml
index 4cd6a9760..9160b7b8b 100644
--- a/reference/legacy.yaml
+++ b/reference/legacy.yaml
@@ -2275,6 +2275,35 @@ solum:
       repos:
         - openstack/solum-tempest-plugin
 
+sunbeam:
+  irc-channel: openstack-sunbeam
+  service: Deployment and operational tooling for OpenStack
+  url: https://opendev.org/openstack/sunbeam-charms/src/branch/main/ops-sunbeam/README.rst
+  partial: yes
+  deliverables:
+    sunbeam-charms:
+      retired-on: 2024-04-30
+      repos:
+        - openstack/charm-aodh-k8s
+        - openstack/charm-barbican-k8s
+        - openstack/charm-ceilometer-k8s
+        - openstack/charm-cinder-ceph-k8s
+        - openstack/charm-cinder-k8s
+        - openstack/charm-designate-bind-k8s
+        - openstack/charm-designate-k8s
+        - openstack/charm-glance-k8s
+        - openstack/charm-gnocchi-k8s
+        - openstack/charm-heat-k8s
+        - openstack/charm-horizon-k8s
+        - openstack/charm-keystone-k8s
+        - openstack/charm-magnum-k8s
+        - openstack/charm-neutron-k8s
+        - openstack/charm-nova-k8s
+        - openstack/charm-octavia-k8s
+        - openstack/charm-openstack-hypervisor
+        - openstack/charm-ops-sunbeam
+        - openstack/charm-placement-k8s
+
 swift:
   irc-channel: openstack-swift
   service: Object Storage service
diff --git a/reference/projects.yaml b/reference/projects.yaml
index d34cfa843..683bc8ed5 100644
--- a/reference/projects.yaml
+++ b/reference/projects.yaml
@@ -2391,30 +2391,11 @@ sunbeam:
     containing many 1000's of hypervisors - leveraging a hybrid deployment
     model using Juju to manage both Kubernetes components and machine based
     components through the use of charms.
-  url: https://opendev.org/openstack/charm-ops-sunbeam/src/branch/main/README.rst
+  url: https://opendev.org/openstack/sunbeam-charms/src/branch/main/ops-sunbeam/README.rst
   deliverables:
     sunbeam-charms:
       release-management: external
       repos:
-        - openstack/charm-aodh-k8s
-        - openstack/charm-barbican-k8s
-        - openstack/charm-ceilometer-k8s
-        - openstack/charm-cinder-ceph-k8s
-        - openstack/charm-cinder-k8s
-        - openstack/charm-designate-bind-k8s
-        - openstack/charm-designate-k8s
-        - openstack/charm-glance-k8s
-        - openstack/charm-gnocchi-k8s
-        - openstack/charm-heat-k8s
-        - openstack/charm-horizon-k8s
-        - openstack/charm-keystone-k8s
-        - openstack/charm-magnum-k8s
-        - openstack/charm-neutron-k8s
-        - openstack/charm-nova-k8s
-        - openstack/charm-octavia-k8s
-        - openstack/charm-openstack-hypervisor
-        - openstack/charm-ops-sunbeam
-        - openstack/charm-placement-k8s
         - openstack/sunbeam-charms
 swift:
   ptl:
diff --git a/tools/validate-legacy.py b/tools/validate-legacy.py
index 5e006dda0..7a93c37a5 100755
--- a/tools/validate-legacy.py
+++ b/tools/validate-legacy.py
@@ -20,7 +20,7 @@ import sys
 import requests
 import yaml
 
-FILES_URL = "https://opendev.org/api/v1/repos/{}/git/trees/master"
+FILES_URL = "https://opendev.org/api/v1/repos/{}/git/trees/{}"
 IGNORED_REPOS = [
     # NOTE(gmann): The below list represent the prefix of the old uncleaned
     # retired repositories. They are too many and not worth to cleanup now.
@@ -105,14 +105,26 @@ for team_name, team_data in legacy_projects.items():
                 print(msg)
                 continue
 
-            url = FILES_URL.format(repo)
-            files = requests.get(url).json()
-            file_names = sorted([f['path'] for f in files['tree']])
+            for branch in ('master', 'main'):
+                try:
+                    url = FILES_URL.format(repo, branch)
+                    files = requests.get(url).json()
+                    file_names = sorted([f['path'] for f in files['tree']])
+                    break
+                except KeyError:
+                    # Try with next default branch!
+                    pass
 
-            if file_names != ['.gitreview', 'README.rst']:
-                msg = '{} is not properly retired, files: {}.'.format(
-                    repo, file_names)
-                print(msg)
+            try:
+                for file in file_names:
+                    if file not in ('.gitreview', 'README.rst'):
+                        msg = '{} is not properly retired, files: {}.'.format(
+                            repo, file_names)
+                        print(msg)
+                        errors += 1
+                        continue
+            except NameError:
+                print("Unable to detect default branch")
                 errors += 1
                 continue