It's not so much the police, it's the insurance. If you have an accident and only have a licence from your home country (no IDP) , there's a good chance they won't cover the claim
I have a First Direct bank account in UK without having a UK phone number, the only phone number I have is my Thai one. The bank has no problem with this and have called me on it on numerous occasions.
I was friends with a visa agent for many years and he would never touch a marriage visa because it was too much work. He would always tell his clients retirement visa or nothing.
My advice would be go to immigration with your partner and talk to them direct
A guy I know had his pension stopped twice because he changed address and didn't notify DWP. It was a pita to sort out, his son had to call UK for him in the end