Dudgeon, Mark Bergin, David Parry and Paul Graham are leaving the business to join Deutsche Bank at the end of September.
Senior HBOS executive Nigel Payne will assume full responsibility for TMB as managing director reporting to Nigel Stockton, director of HBOS Intermediary Mortgages. Nigel Payne will be joined by two additional appointments: Peter Charge, appointed as director, sales and John Nixon, appointed as director, operations.
Three other existing senior managers at TMB, John Sleigh, Robert Holmes and Barrie Knox, will all take a wider role at the business.
TMB said it will continue to focus on providing specialist mortgages via intermediaries and packagers.
Nigel Stockton, director of HBOS Intermediary Mortgages, said: "I'm delighted that Nigel will be joining the team at TMB as he has vast experience of the UK mortgage market. He and the team will ensure that TMB goes from strength to strength. Obviously we're sorry to lose Bill and his team but we wish them all the very best in their new roles."
Nigel Payne, managing director of TMB, said: "I'm very much looking forward to joining TMB and taking the business into its next phase of growth. This is a new and very exciting chapter in our history. We are already planning to announce some extremely exciting developments in the next eight weeks."
