The term of office of members and alternate members shall begin on the first day of August of even-numbered years and continue for two years and until their successors are selected and have qualified. The consecutive terms of office of a member shall be limited to two terms. The terms of office of alternate members shall not be so limited. Members, their alternates, and their respective successors shall be nominated and selected by the Secretary as provided in §§ 905.22 and 905.23.