Maybe I'm looking at a different guide than you, but I'm not seeing any way for qbittorrent to auto update the forwarded port from Proton. Everytime your VPN connection resets (either from reboot or just a dropped connection), you have to manually update the port in qbittorrent. Of course there are some scripts that can do this for you.
You can disable the update check in the config file. Then just update with your package manager as usual and forget about it.