As used in this article the following terms shall have the following meanings:
The determination of whether premises meet the requirements for eligibility set forth in this subdivision shall be made as of the effective date of the certification of eligibility issued pursuant to section twenty-five-z of this article. Notwithstanding the provisions of paragraphs one and two of this subdivision, if, subsequent to such date, the property in which such premises are contained ceases to meet the requirements of paragraph one or two of this subdivision, such premises shall nonetheless remain eligible premises, provided that the eligible business continues to occupy such premises; provided however that if, after such property ceases to meet the requirements of paragraph one or two, an eligible business first leases or purchases additional premises contained in such property, such additional premises shall not be considered eligible premises unless they meet the requirements of paragraph three of this subdivision.
N.Y. Gen. City Law § 25-Y