If you're using distribution packages for WireGuard (whether they're in the official repos or not), they should be rebuilt with each kernel upgrade and so you s

If you're using distribution packages for WireGuard (whether they're in the official repos or not), they should be rebuilt with each kernel upgrade and so you shouldn't be having any issues with stability. But yes, if you upgrade to a kernel where WireGuard is part of the main kernel package (even if it's backported by your distribution) then you wouldn't have those issues either.