72 Pa. Stat. § 5574.7
The act, approved the fourteenth day of April, one thousand nine hundred and thirty-seven (Pamphlet Laws, three hundred two), the act, approved the twenty-sixth day of May, one thousand nine hundred and thirty-seven (Pamphlet Laws, eight hundred ninety-three), the act, approved the twenty-fifth day of October, one thousand nine hundred and thirty-eight (Pamphlet Laws, eighty-four), the act, approved the twenty-fifth day of October, one thousand nine hundred and thirty-eight (Pamphlet Laws, eighty-eight) and the act, approved the nineteenth day of June, one thousand nine hundred and thirty-nine (Pamphlet Laws, four hundred five) shall continue in full force and effect as to any and all taxpayers who have taken advantage of and are not in default in the provisions thereof. All other acts and parts of acts, general, local and special, inconsistent herewith be and the same are hereby suspended during the time this act shall be in effect.
72 P.S. § 5574.7