Any approval or authorization issued pursuant to this chapter shall lapse within 18 months of the date of approval unless, prior to that date, a building permit or certificate of occupancy has been issued or an extension as provided in Subsection B has been requested.

Prior to the expiration of the period of authorization provided for in Subsection A, an applicant may request that such period be extended for a period of 12 months from the date of expiration or extension thereof. Absent a material change in relevant conditions surrounding the original approval, the authorizing board shall grant such extension. Any further extension may only be granted upon a showing of good cause by the applicant, which good cause may include a continued absence of material changes surrounding the original approval and/or factors beyond control of the applicant. Any further extension shall be for such duration as deemed appropriate by the approving board but shall not exceed 12 months.