The term of every educational service district board member shall begin on the second Monday in January next following the election at which he or she was elected: PROVIDED, That a person elected to less than a full term pursuant to this section shall take office as soon as the election returns have been certified and he or she has qualified. In the event of a vacancy in the board from any cause, such vacancy shall be filled by appointment of a person from the same board-member district by the educational service district board. In the event that there are more than three vacancies in a seven-member board or four vacancies in a nine-member board, the Washington state school directors' association president shall fill by appointment sufficient vacancies so that there shall be a quorum of the board serving. Each appointed board member shall serve until his or her successor has been elected at the next election called by the executive director of the Washington state school directors' association and has qualified.