Debian will probably ship it as a module, like the other networking modules they ship, which means as long as they don't change ABI, after your `apt upgrade`, y

Debian will probably ship it as a module, like the other networking modules they ship, which means as long as they don't change ABI, after your `apt upgrade`, you can do the usual `rmmod wireguard && modprobe wireguard` to hot-load the new version at runtime without having to reboot.