(a) The terms of all governors and trustees which are limited shall, unless otherwise expressly provided herein, commence on July 1 in the first year, and end on June 30 in the last year, of such term.
(b) In case a governor or a trustee is elected president and he thereby becomes a nonvoting governor or trustee ex officio, a vacancy in his prior office as governor or trustee shall thereby occur.
(c) In case a trustee is appointed a governor by the Governor of the State, a vacancy in his prior office as trustee shall thereby occur.
(d) Any vacancy occurring during the term of any governor or trustee (other than by the expiration of his term) shall be filled for the unexpired term only, in the same manner and subject to the same provisions, as in the case of his appointment or election; subject, however, to the provisions of subsection I.d. of section 18A:65-15.