OpenWRT Wireguard S2S Requires Reboot Monthly

I have 2x Netgear R6260 routers running OpenWRT. One is running version 23.05.3 (Site A) and the other is running 22.03.5 (Site B). Both sites have their own dedicated Internet connection. I use DDNS at both sites since I don't have static IPs. There is a Wireguard tunnel configured on both to connect them. I have had this set up for 1+ years and consistently have the following issue:

Every month or so I discover that the Wireguard tunnel has gone down. Site A shows that it is transmitting, but not receiving. Site B shows that it is transmitting and receiving successfully. Restarting the Wireguard interface on both ends does nothing. The only solution is to restart the entire router at Site A. Restarting Site B does nothing.

What could be causing this drop to happen and where can I find pertinent logs to see why Site A is suddenly not receiving (or potentially blocking?) the traffic from Site B?

Check logs (probably if you forward them to log serbrr at stable side last entries tell something)
restarting router means new dhcp or ppp session. Smth like ifup wan may help.

Did the IP address change?
When using DDNS, you need to enable wireguard_watchdog as described in the commit message.

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