Within the Large-Scale Plan Subdistrict A, Subareas B1 and B2 of the Farley Corridor Subdistrict B, and the South of Port Authority Subdistrict E, residential use shall be permitted only upon certification of the Chairperson of the City Planning Commission that the zoning lot on which such residential use is located contains the minimum amount of commercial floor area required before residential use is allowed, as specified in Section 93-21 (Floor Area Regulations in the Large-Scale Plan Subdistrict A) or 93-22 (Floor Area Regulations in Subdistricts B, C, D, E and F), as applicable, and that for zoning lots in Subareas A2 through A5 of the Large-Scale Plan Subdistrict A, a certification pursuant to Section 93-34 (Distribution of Floor Area in the Large-Scale Plan Subdistrict A) has been made.

However, special regulations shall apply to zoning lots with phased development, as follows:

(a)        except as provided in paragraph (c) of this Section, for zoning lots with less than 69,000 square feet of lot area, the Chairperson shall allow for phased development, upon certification that a plan has been submitted whereby the ratio of commercial floor area to residential floor area, in buildings in each phase, is no smaller than the ratio of the minimum amount of commercial floor area required on the zoning lot before residential use is allowed, to the maximum residential floor area permitted on the zoning lot as specified in Section 93-21 or 93-22, as applicable;

(b)        for zoning lots with at least 69,000 square feet of lot area, the Chairperson shall allow for one or more buildings containing residences to be developed or enlarged without the minimum amount of commercial floor area required before residential use is allowed, as specified in Section 93-21 or 93-22, as applicable, upon certification that a plan has been submitted whereby one or more regularly shaped portions of the zoning lot with a minimum area of 50,000 square feet are reserved for future development of not more than two million square feet of commercial floor area on each such portion, and that, upon full development of such zoning lot, the ratio of commercial floor area to residential floor area shall be no smaller than the ratio of the minimum amount of commercial floor area required on the zoning lot before residential use is allowed, to the maximum residential floor area permitted on the zoning lot, as specified in Section 93-21 or 93-22, as applicable; and

(c)        for zoning lots with at least 55,000 square feet but less than 69,000 square feet of lot area within Subarea A3 of the Large-Scale Plan Subdistrict A, the Chairperson shall allow for one or more buildings containing residences to be developed or enlarged without the minimum amount of commercial floor area required before residential use is allowed, as specified in paragraph (a) of Section 93-21, upon certification that a plan has been submitted whereby one or more regularly shaped portions of the zoning lot with a minimum area of 35,000 square feet are reserved for future development, and that, upon full development of such zoning lot, the ratio of commercial floor area to residential floor area shall be no smaller than the ratio of the minimum amount of commercial floor area required on the zoning lot before residential use is allowed, to the maximum residential floor area permitted on the zoning lot, as specified in Section 93-21.

All developments or enlargements so certified shall be permitted only in accordance with the provisions of this Chapter.