(1) Each city organized and governed under the mayor-council plan shall have a mayor and each shall have a legislative body composed of not less than six (6) nor more than twelve (12) members as prescribed by ordinance. An ordinance amending the number of legislative body members shall be:
(a) Enacted and filed with the county clerk of any county or counties in which the city is located by no later than the first Wednesday after the first Monday in November of the year preceding the year in which the legislative offices will appear on the ballot; and (b) Crafted in such a manner that the amended number of legislative body members becomes effective on January 1 of the year following the election of the number of legislative body members specified in the amending ordinance.
(2) Each city organized and governed under the commission plan or city manager plan shall have a legislative body composed of a mayor and four (4) commissioners.