After 22.01 upgrade, dual WAN not failing back

manicmoose

Was running 2.5.2 for ages and dual WAN in a gateway group worked great.
Upgraded to 2.6.0, then 22.01.
Today my main WAN failed and pfsense flicked over to 2nd'ary - no problem.

When the main WAN came back up, pfsense failed to acknowledge that it was back up - the gateway still "appeared" to be down, even though it DID have an IP address.
Was getting heaps of the following "arpresolve" messages both before and after this snippet from 'system.log':

Feb 24 10:07:06 fw kernel: arpresolve: can't allocate llinfo for <redacted_IP> on igb0
Feb 24 10:07:08 fw check_reload_status[974]: Linkup starting igb0
Feb 24 10:07:08 fw kernel: igb0: link state changed to UP
Feb 24 10:07:09 fw php-fpm[7129]: /rc.linkup: DEVD Ethernet attached event for wan
Feb 24 10:07:09 fw php-fpm[7129]: /rc.linkup: HOTPLUG: Configuring interface wan
Feb 24 10:07:15 fw kernel: igb0: link state changed to DOWN
Feb 24 10:07:15 fw check_reload_status[974]: Linkup starting igb0
Feb 24 10:07:29 fw kernel: igb0: link state changed to UP
Feb 24 10:07:29 fw check_reload_status[974]: Linkup starting igb0
Feb 24 10:07:49 fw kernel: arpresolve: can't allocate llinfo for <redacted_IP> on igb0
Feb 24 10:07:49 fw kernel: arpresolve: can't allocate llinfo for <redacted_IP> on igb0
Feb 24 10:07:49 fw kernel: arpresolve: can't allocate llinfo for <redacted_IP> on igb0
Feb 24 10:07:50 fw kernel: arpresolve: can't allocate llinfo for <redacted_IP> on igb0
Feb 24 10:07:50 fw kernel: arpresolve: can't allocate llinfo for <redacted_IP> on igb0
Feb 24 10:07:51 fw kernel: arpresolve: can't allocate llinfo for <redacted_IP> on igb0

igb0 being my primary WAN (obs).

I re-started the gateway daemon and straight away pfsense noticed WAN was up and started using it again.

I will try to recreate this again (when I have a suitable opportunity), but is there anything specific I should look out for, or info I can grab that might help narrow this down?

Thanks.