The terms of the regular members shall be four years from January 1 of the year of their appointment. Nothing in this subsection shall, however, be construed to affect the term of any present member of the Board of Adjustment, all of whom shall continue in office until the completion of the term for which they were appointed.

The terms of the alternate members shall be two years from January 1 of the year of their appointment.

Alternate members shall be designated at the time of appointment as "Alternate No. 1" and "Alternate No. 2."

Alternate members may participate in discussions of the proceedings but may not vote except in the absence or disqualification of a regular member. A vote shall not be delayed in order that a regular member may vote instead of an alternate member. In the event that a choice must be made as to which alternate member is to vote, Alternate No. 1 shall vote.

No regular or alternate member of the Board of Adjustment may hold any elective office or position under the municipality, except that one such regular member may be a member of the Planning Board.