Md. Code, Tax-Prop. § 14-832.1
In Queen Anne's County, whenever, prior to July 1, 1985, any property was sold for the nonpayment of any taxes and the sale has not been ratified and confirmed, any purchaser at the prior tax sale may proceed under the provisions of this subtitle to foreclose all rights of redemption in the property purchased. The collector, upon surrender of a receipt or of any other instrument evidencing payment of the necessary part of the purchase price, shall deliver to the purchaser a certificate signed by the collector containing all available information concerning the prior sale. Any certificate issued under this subtitle shall have the same force and effect as other certificates issued under the provisions of this subtitle and shall be subject to all of the provisions of this subtitle relating to any other certificates of sale. Any collector may issue the certificate provided for in this subtitle, notwithstanding the fact that any prior tax sale was made by one of the collector's predecessors in office. The provisions of this subtitle may not affect the right of any purchaser at a tax sale held prior to July 1, 1985 to proceed under the provisions of laws existing prior to July 1, 1985. Any purchaser may, at the option of the purchaser, proceed under the provisions of this subtitle or under the provisions of such prior existing laws.
Md. Code, TP § 14-832.1