(a) The Department may divide such of the election districts, and such only, as by the election last preceding such division shall be found to contain a greater number of voters than can conveniently vote therein. Each election district so divided shall be at all times wholly within boundaries of 1 representative district.
(b) The Department shall designate each election district by an appropriate title that will distinguish it from every other election district.
(c) The division of election districts shall be made at any time after a general election is held and before March 1 of the next succeeding general election year.