diff --git a/networking_ccloud/tools/netbox_config_gen.py b/networking_ccloud/tools/netbox_config_gen.py
index 3c8168f6..3f2b4ecb 100644
--- a/networking_ccloud/tools/netbox_config_gen.py
+++ b/networking_ccloud/tools/netbox_config_gen.py
@@ -382,15 +382,6 @@ def make_infra_networks_and_extra_vlans(self, iface: NbRecord, svis: Dict[NbReco
                 extra_vlans.add(vlan.vid)
                 continue
 
-            # by convention we ignore certain VLAN groups member VLANs, once we upgrade to netbox 3.x we shall remove
-            # this as VLAN groups will then support tags
-            if vlan.group and (
-                    (vlan.group.slug.startswith(self.region) and vlan.group.slug.endswith('cp'))
-                    or vlan.group.slug == f'{self.region}-regional'
-                    or vlan.group.slug == 'global-cc-core-transit'):
-                extra_vlans.add(vlan.vid)
-                continue
-
             mandatory_attrs = ('vid', 'tenant')
             for attr in mandatory_attrs:
                 if not getattr(vlan, attr, None):
@@ -486,7 +477,7 @@ def get_l3_data(self, asn_region: int, pod: int, switchgroup_no: int, leaf_no: i
 
     def get_asn_region(self, region):
         sites = self.netbox.dcim.sites.filter(region=region)
-        site_asns = {site.asn for site in sites if site.asn}
+        site_asns = {asn for site in sites if site.asns for asn in site.asns}
         if not site_asns:
             raise ConfigException(f"Region {region} has no ASN")
         if len(site_asns) > 1:
@@ -571,10 +562,14 @@ def get_connected_devices(self, switches: List[NbRecord]) -> Tuple[Set[NbRecord]
                     continue
 
                 # FIXME: ignore management, peerlink (maybe), unconnected ports
-                if iface.connected_endpoint is None:
+                if iface.connected_endpoints is None:
                     continue
 
-                far_device = iface.connected_endpoint.device
+                if len(iface.connected_endpoints) > 1:
+                    raise ConfigException(f'Interface {iface.name} on {switch.name} has more than one '
+                                          'connected endpoint')
+
+                far_device = iface.connected_endpoints[0].device
                 if far_device.device_role.slug not in self.connection_roles:
                     continue
                 if (far_device.device_role.slug == 'filer'
@@ -586,7 +581,7 @@ def get_connected_devices(self, switches: List[NbRecord]) -> Tuple[Set[NbRecord]
 
                 if self.verbose:
                     print(f"Device {switch.name} port {iface.name} is connected to "
-                          f"device {far_device.name} port {iface.connected_endpoint.name} "
+                          f"device {far_device.name} port {iface.connected_endpoints[0].name} "
                           f"role {far_device.device_role.name}")
 
                 ports_to_device = device_ports_map.get(far_device, [])
@@ -636,8 +631,13 @@ def get_interconnect_hostgroups(self, nb_switches: List[NbRecord]) -> List[conf.
                 ifaces = self._ignore_filter(self.netbox.dcim.interfaces.filter(device_id=nb_switch.id))
                 aci_facing_ifaces = list()
                 for iface in ifaces:
-                    connected_device_role = iface
-                    for attr in ('connected_endpoint', 'device', 'device_role', 'slug'):
+                    if not iface.connected_endpoints:
+                        continue
+                    if len(iface.connected_endpoints) > 1:
+                        raise ConfigException(f'Interface {iface.name} on {nb_switch.name} has more than '
+                                              'one connected endpoint')
+                    connected_device_role = iface.connected_endpoints[0]
+                    for attr in ('device', 'device_role', 'slug'):
                         connected_device_role = getattr(connected_device_role, attr, None)
                     if not connected_device_role:
                         continue