(1) Following the effective date of a conversion of a transit authority established under the Transit Authority Law into a regional metropolitan transit authority, the election commissioner or county clerk of the county in which the majority of the territory of the authority is located shall divide the territory of the authority into seven numbered districts for the purpose of electing members to the board. Such districts shall be compact and contiguous and substantially equal in population. The newly established districts shall be certified to the Secretary of State following such creation. The newly established districts shall apply beginning with the nomination and election of board members at the next statewide primary and general elections held at least seventy days after the effective date of such conversion. Following the drawing of initial districts pursuant to this section, additional redistricting shall be undertaken by the board according to section 32-553. One member shall be elected from each district as provided in section 32-551.

(2) Upon the joining of a municipality or municipalities to an existing regional metropolitan transit authority by agreement pursuant to subdivision (2)(a) of section 18-804, or upon a municipality leaving such regional metropolitan transit authority by vote pursuant to subdivision (2)(b) of section 18-804, the board shall redraw the boundaries of the districts to ensure that such districts remain compact and contiguous and substantially equal in population. The redrawn districts shall be certified to the Secretary of State within six months following the joining or leaving of such municipality or municipalities and shall apply beginning with the nomination and election of board members at the next statewide primary and general elections held at least seventy days after the certification of the districts.

(3) A vacancy in office for an elected member of the board shall occur as set forth in section 32-560. Whenever any such vacancy occurs, the remaining members of the board shall appoint an individual residing within the geographical boundaries of the district in which the vacancy occurred for the balance of the unexpired term.