(1) Unless the articles of incorporation provide otherwise, if a vacancy occurs on a board of directors, including a vacancy resulting from an increase in the number of directors: the shareholders may fill the vacancy;
(2) the board of directors may fill the vacancy; or
(3) if the directors remaining in office constitute fewer than a quorum of the board, they may fill the vacancy by the affirmative vote of a majority of all the directors remaining in office.
(4) If the vacant office was held by a director elected by a voting group of shareholders, only the holders of shares of that voting group are entitled to vote to fill the vacancy if it is filled by the shareholders.
(5) A vacancy that will occur at a specific later date (by reason of a resignation effective at a later date under § 4-27-807(b) or otherwise) may be filled before the vacancy occurs but the new director may not take office until the vacancy occurs.