No lien upon real estate for taxes and levies due and payable to the Commonwealth or any political subdivision thereof which has been, or shall hereafter become, delinquent for twenty or more years shall be enforced in any proceeding at law or in equity and such lien shall be deemed to have expired and to be barred and cancelled after such time. For purposes of this section, taxes deferred pursuant to an ordinance enacted in conformity with Article 2 (§ 58.1-3210 et seq.) or Article 2.1 (§ 58.1-3219 et seq.) of Chapter 32 of this title shall not be considered “delinquent” during the pendency of any period of deferral, and the lien upon real property for taxes and levies shall remain valid for twenty years plus any period of deferral afforded pursuant to such ordinance. The right, title and interest of the Commonwealth in and to all real estate sold for taxes and levies which have been, or hereafter become, delinquent for twenty or more years, when such real estate has been purchased by the Commonwealth and not resold, is hereby unconditionally released unto and vested by operation of law in the person or persons who owned the real estate at the time the Commonwealth so acquired title or persons claiming, or to claim, by, through or under them. No clerk shall make a tax deed conveying to any person any real estate sold for delinquent taxes or levies which have been, or hereafter become, delinquent for twenty or more years.