The minefield that is the Oxbridge MA does not stop at BA graduates being awarded the degree simply for keeping their noses clean for a few years after graduating. Under current statutes, the University of Cambridge may award an MA to anyone "who has been admitted to some office in the university, or to a headship or fellowship of a college, or who holds a post in the University Press".
Similar conditions apply at Oxford. In addition, Oxford, Cambridge and Trinity College, Dublin, have an arrangement whereby graduates of one can automatically be awarded the same level of degree from an-other. Something to keep the Quality Assurance Agency busy for a while yet.