(b)the jagirdar or his successor in interest for the time being has, by written instrument duly executed by him, either before or after the passing of this Act, signified, on behalf of himself and his family, acceptance of the rule of descent to be so declared, and either no succession has taken place since such acceptance, or else in any successions which have taken place, since such acceptance the jagir has in fact not devolved otherwise than it would have devolved had the said rule of descent been in force.