In the event that a lot shall have been lawfully created by filed map or deed prior to the date of the first ordinance of the Township requiring approval of a subdivision by the Planning Board or by a perfected subdivision approval by the Planning Board, no variance shall be required for the proposed development of such lot merely because the lot is deficient in area or width pursuant to this article, provided that the proposed development shall be shown to meet all setback, height and coverage restrictions of this article.