In Appeal of Hawcrest Association, 399 Pa. 84, 87, 160 A.2d 240, 242 (1960), the court found that the amendment "did not add or delete any permitted use; it did not change a district boundary or classification, nor did it vary any regulation." Id. Therefore, the Court found that the amendment was insubstantial, and refused to invalidate the zoning ordinance at issue, even though it had not been re-advertised following the amendment. The Commonwealth Court reached a different conclusion on substantiality in Save Our Local Environment II v. Foster Township Board of Supervisors, 137 Pa.Cmwlth. 505, 508-09, 587 A.2d 30, 31-32 (1991), holding that modification of a zoning district from agricultural to industrial amounts to a substantial change when applied to 3,300 acres.