(1) Unless otherwise specified by the Board, a special exception or variance shall expire if the applicant fails to obtain a building permit within six months from the date of authorization thereof. If subdivision or land development approval is required to implement the special exception or variance, the six-month period shall begin to run on the date of the Board's approval or on the date final subdivision or land development approval is granted, whichever shall last occur, provided that the subdivision or land development application is submitted within six months of the Zoning Hearing Board decision.

(2) A use permitted by special exception or variance shall expire if the use authorized is abandoned. If such use permitted by special exception or variance is discontinued by nonuse, unlawful use or a change of use to one not authorized by the previously obtained special exception or variance or by this chapter as of right for a continuous period of six months or more, the abandonment of such use shall be presumed, and any subsequent use of such building or land shall be in conformity with the provisions of this chapter.