72 Pa. Stat. § 5575.6
In order to enable the taxpayer or owner having the right of redemption under a tax sale to receive the full benefits of this act, no real property shall be sold for nonpayment of taxes before November first, one thousand nine hundred and forty-three, except in counties of the second class, the county treasurer, and in cities of the second class, the city treasurer, may hold their respective tax sales of real property as provided by existing law, unless the owner of any such property to be sold at any such sale, or any one interested in such property, shall, prior to such sale, pay the first installment, as hereinbefore provided, of the delinquent taxes charged against such property, and for which it is to be sold. If the first installment of any such taxes shall be paid in order to prevent the tax sale as aforesaid, the taxpayer making such payment shall still be required to pay the current taxes before they become delinquent as hereinbefore provided in order to secure the benefits of this act. Any tax sale shall be adjourned or readjourned, or right of redemption extended as often as may be necessary, for the purpose of this section. If any tax sale is adjourned or readjourned, or right of redemption extended after advertisement or sale, no additional advertisement or notice shall be necessary for the adjourned or readjourned sale or right of redemption. No such adjournment or readjournment or redemption, failure to advertise or hold any such tax sale, shall invalidate the lien of any tax due and unpaid or sale had subject to redemption, but the lien of all such taxes shall be fully preserved during the entire installment period herein provided for if the taxpayer avails himself of the privileges or benefits of this act: Provided, however, That in every case where a taxpayer avails himself of the privileges or benefits of this act, the period during which payment of the said delinquent taxes is postponed or continued under this act shall not be included in computing and determining whether or not any right of the tax assessing and levying authority has been barred or lost by reason of the provisions of any statute or statutes now existing or hereafter enacted limiting the right of the said tax levying and assessing authorities to file, preserve or maintain the lien of the said taxes.
72 P.S. § 5575.6