(a) General rule.--If council, by ordinance, divides any borough into wards, erects new wards out of two or more wards or parts of wards or divides a ward already erected into two or more wards, the ordinance shall provide for the election of an equal number of members of council, in each of the wards, in a manner as not to interfere with the terms of those previously elected.

(b) Election of members.--The following shall apply:

(1) If a borough is first divided into wards, the ordinance providing for the division shall fix the number of members of council in each ward at not more than two. If the entire number of council is to be composed of an even number, one-half of the entire number must be elected at each municipal election. If the entire number of council is to be an odd number, the ordinance shall establish two classes and provide that one-half of the entire number of members of council, less one, shall, as soon as possible, take their office in a year divisible by four, and the remaining number of members of council shall take their office in an even-numbered year not divisible by four.

(2) The apportionment under paragraph (1) shall be equal or as nearly equal as possible representation by wards in each class. Biennially, at each municipal election, a sufficient number of members of council shall be elected, for the term of four years from the first Monday of January succeeding the election, to fill the places of those whose terms shall expire on the first Monday of January following the election.