It never was and according to the BOE it still isnt
"The deposit protection limit applies to the total eligible deposits of each person, per PRA-authorised firm. So for deposits in a joint account, this means that each account holder is protected up to the deposit protection limit, ie the total protection adds up to two times £85,000.
A PRA-authorised firm may own several banking and building society brands. This means that anyone who has deposits in more than one account under a single brand, or multiple accounts under different brands owned by a single firm, is only protected up to a total of £85,000 across all these accounts."
The most obvious one that people should avoid would be Halifax and Bank of scotland who share the PRA code, but there are others there