Ben Thompson (pictured) is moving from his current role as group managing director to become the deputy chief executive.
Thompson is the former chief executive of ULS and managing director of the Legal & General Mortgage Club, and joined MAB a year ago.
Lucy Tilley is moving from her current position as finance director to become chief financial officer.
In a statement, the firm said: “These appointments reflect the scale and ambitions of the group.”
The changes, which will take place on 1st July, will coincide with David Preece’s retirement from his role as executive director, though he will retain a spot as non-executive director of the group.