poacher turned gamekeeper
British
someone whose job seems to involve working against the person who is now doing the job which they did before.
He used to be the the union rep but now he's in management - a case of poacher turned gamekeeper.
poacher turned gamekeeper
British
someone whose job seems to involve working against the person who is now doing the job which they did before.
He used to be the the union rep but now he's in management - a case of poacher turned gamekeeper.
Cambridge English Idioms Dictionary