A. The exact location of any disputed zoning district boundary line shall be determined by the zoning hearing board.
B. Where a lot, held in single and separate ownership at the effective date of this chapter, is divided by a district boundary line, the uses permitted in the less restrictive district may extend into that portion of said lot in the more restrictive district provided that neither district is a residential district. The yard, lot coverage and other regulations of the more restrictive district shall apply to the portion of the lot where the less restrictive use has been extended.