Organization. The Zoning Board of Appeals, hereinbefore created pursuant to § 267 of Town Law, shall be comprised of five members. To the extent the Zoning Board of Appeals consists of more than five members as of the date of adoption of this subsection, each member shall continue to hold office until the expiration of his or her present term. Zoning Board of Appeals members shall be appointed by the Town Board for a term of five years, which shall also designate the Chairman thereof, for such terms as provided by the Town Law and any amendments thereto and shall have all the powers and perform all the duties prescribed by statute and by this chapter. Each member of the Zoning Board of Appeals shall continue to hold office until the expiration of his or her present term, at which time the Town Board shall appoint a successor so as to maintain the Zoning Board of Appeals at five members. If a vacancy shall occur other than by expiration of a term, it shall be filled by the Town Board by appointment for the unexpired term, provided no successor shall be appointed, nor shall any appointments otherwise be made, where such an appointment would cause the Zoning Board of Appeals to be comprised of greater than five members. The Town Board may appoint no more than one person to serve on both the Planning Board and the Zoning Board of Appeals concurrently. Said Board shall establish and from time to time amend or repeal rules and regulations for the effectuation of its powers and duties.