Election of board of education in towns adopting biennial elections. Alternate rotation of terms and length of terms permitted

(a) In any town having a board of education of three, six, nine or twelve members established in accordance with the general statutes which has adopted biennial elections, at each such election one-third of the members of such board shall be elected for a term of six years. In any town having any such board which adopts biennial elections, at its first biennial election sufficient members of the board of education shall be elected to fill the entire number of positions on said board for terms as follows: One-third shall be elected for a term of two years, one-third shall be elected for a term of four years and one-third shall be elected for a term of six years. At each biennial election thereafter, one-third of the members of such board shall be elected for a term of six years. (b) Notwithstanding any provision of the general statutes to the contrary, any town having a board of education of three, six, nine or twelve members established in accordance with the general statutes which has adopted biennial elections may, by charter provision or by ordinance, establish a different method of rotation and a different length of the term of office. Such ordinance or charter provision shall take effect at the next regular town election following the effective date of such ordinance or charter provision.