Is anyone else having issues logging into iCloud via quic?

Helping a friend with their issues and I'm able to on my quic connection but they can't on theirs. We've tried two routers using PPOE no VLAN and it's only started lately. Apple say it's not them at it works fine on the same machine using 4G or another internet connection.

The same issue is repeatable on another Mac in the house so I don't think it's a machine specific issue. Esp if it works on a different connection.

Their IP is 118.67.194.58

Is anyone from @quic able to have a look based on their IP pls?