BQM on 3 5G stopped working

I have been using BQM on my 3 5G connection for a few months now without a problem. Last night I received a new IPv4 address from 3 and my DDNS updated successfully, however I am now getting a fully red graph. Editing the BQM details to the new IPv4 address does not help and nothing has changed settings or firmware wise on the modem or eero router overnight. Wondering if 3 have suddenly stopped passing icmp requests through or whether it could be something else.

Have you moved onto a CGNAT IP address? What are the first octets of your address?

Thanks
That may be it although I am still on 3internet apn
This is the new ip address 188.28.112.xxx

Doesn't appear to be an obvious CGNAT address...

Perhaps time to ask 3 - good luck!

Yes, I was just able to check and the previous address that worked was in a similar range 188.30.128.xxx.