I dont know what exactly happens and what this causes. As stated XR819 is known to be unstable or even considerable broken by design (like PCIe on H6 but at least it works somehow). I own the board by myself but the first thing I did was removing the wireless antenna as I did not need it
Anyway. Sure you can script yourself some kind a watchdog that checks by pinging a host outside every second or so and when a disconnect happens do something like ifdown/ifup if that helps or do forcefully rmmod and modprobe the wireless module to recover it (if that works at all, no idea). You have to try around by yourself. Maybe you can come up with something nice.
