If a statute imposes congressional district residency requirements for members of or appointees to a board, commission, council, committee, authority or other governmental body and the boundaries of congressional districts are changed in such a way that the requirements are no longer met, each member serving at the time of the change in district boundaries shall continue to serve the remainder of the member’s current term and until a successor is appointed and qualifies unless the member’s position becomes vacant before the end of such term. Unless otherwise provided by law, upon any vacancy on the governmental body, appointment to fill the vacancy shall be made in such a manner that the residency requirements are met in the least time possible.