AR300M wireguard unstable on latest firmware v3.24

Hi, I have been using wireguard client on firmware v3.19 and work really well (uptime more than a week). But recently I updated to v3.24 (and also beta v3.26) and I got disconnected with unsuccessful automatic retry within less than 12 hours. The only solution is to stop automatic retry and then manually reconnect.
Unfortunately I could not get the logs about when this disconnect happened. The log itself was already full with error for stubby.
This v3.24 is great with additional MTU option, which I need the most since GCP wireguard server limit the MTU, and also VPN policy that looks great. Please help me to stick with this new version

Which WireGuard Server are you using for? Setup by yourself or use 3rd party VPN provider?

I setup WireGuard Server using Google cloud platform (gcp) by myself. I am aware about low mtu from it (1380) but it could be altered using mtu setting in router (1360). That’s how it used to work in firmware v3.19

You can upgrade to latest testing firmware, which support setting mtu on webUI.