There you're into the zone where the reappointment is the prerogative of the Governor in Council, so it is the Governor in Council's prerogative to decide who is reappointed to the board.
From an operational point of view, there is no doubt that an experienced board member is able to deal with more cases than a person who is newly appointed, until such time as that person is up to speed. So for a period of about 6 to 12 months, the productivity of a newly appointed person is noticeably less than the productivity of a person who is an experienced board member.