Members of the Zoning Board of Appeals of the Town of Hamptonburgh now holding office shall, upon expiration of their term, hold office until December 31 of that year. Upon the expiration of the aforesaid members' respective terms, their respective successors shall be appointed by resolution of the Town Board of the Town of Hamptonburgh for terms equal in years to the number of members of the Board, which, pursuant to this article, shall be five members.