Plats and plans previously recorded pursuant to subsections A, B, and C of § 55.1-1916 may be used in lieu of new plats and plans to satisfy in whole or in part the requirements of subsection B of § 55.1-1918, subsection B of § 55.1-1924, or § 55.1-1926 if certifications of such plats and plans are recorded by the declarant in accordance with subsections A and B of § 55.1-1920; and if such certifications are recorded, the plats and plans that they certify shall be deemed recorded pursuant to subsection C of § 55.1-1920 within the meaning of §§ 55.1-1918, 55.1-1924, and 55.1-1926. All condominium instruments for condominiums created prior to July 1, 1991, are hereby validated notwithstanding that the plats were prerecorded as if in compliance with this section and not recorded with amendments converting convertible land or adding additional land if the plats or subsequent amendments contained the required certifications.