You will be aware that you cannot open a U.K. bank account (Wise excepted) unless you are resident in the OK.
Logic suggests that it is not a huge step to then review EXISTING accounts and - possibly - seek to close accounts of non-residents. I understand that the reason relates to increased regulatory requirements for such customers.
I am not personally aware of any institution openly coming out and saying “off you go”. Nevertheless, I have always advocated maintaining a U.K. correspondence address……and at least one U.K. bank.
Personally, I think you will be OK - but it may still be worth considering using a relatives UK address.
At the last count I had active accounts with 4 banks, 10 different credit cards, with credit limits of £90,000, 2 Premium Bond accounts and I remain on the books of the local doctor. I have lived in Thailand for 16 years.