Firmware upgrade for Android 13 may break SSL VPN tunnels

There are a few steps advertised on the web  such as : https://www.getdroidtips.com/android-13-vpn-not-working/

But for Draytek routers- Go to the SSL VPN >> General Setup tab –  and try to change the  port from 443  to something else eg  8443 – see fig 1 below