Hi Fraser,
Update: MW3 much better now, only got the in game network error 2 or 3 times one day. Yesterday had no problems. Now the OpenVPN problem is back, today I've been disconnected from the internet twice already with two different VPN configs. I ended up changing the WiFi to my mesh network that is connected to the R3 so I could work. Is there anything I can try? The R3 is basically a default setup, only added the PS5 to the Geo-Filter.