(a)          In M1-5 and M1-6 Districts located within the rectangle formed by West 23rd Street, Fifth Avenue, West 31st Street and Eighth Avenue, no new dwelling units shall be permitted.  However, dwelling units which the Chairperson of the City Planning Commission determines were occupied on September 1, 1980, shall be a permitted use provided that a complete application for a determination of occupancy is filed by the owner of the building or the occupant of a dwelling unit in such building not later than June 21, 1983. For the purposes of Article 7C of the New York State Multiple Dwelling Law, such a determination of residential occupancy on September 1, 1980, shall be deemed to permit residential use as-of-right for such dwelling units.

All dwelling units permitted pursuant to this paragraph (a) shall be required to comply with the requirements of Section 15-024 (Special bulk regulations for certain pre-existing dwelling units, and joint living-work quarters for artists) where applicable.

Where the Chairperson of the City Planning Commission has determined that floor area was occupied as dwelling units on September 1, 1980, and where such dwelling units are located in a building which, on the date of application to the Department of City Planning under the provisions of this Section, also has floor area which is occupied by referenced commercial and manufacturing uses,  the Chairperson may permit that any floor area in the building be used for dwelling units provided that:

(1)        the total amount of floor area to be used for dwelling units does not exceed the amount of floor area occupied as dwelling units on September 1, 1980;

(2)       referenced commercial and manufacturing uses located on floor area to be used for dwelling units that has been offered a new or amended lease within the building, with a minimum term of two years from the date of application, at a fair market rental for the same amount of floor area previously occupied, and such lease is not subject to cancellation by the landlord;

(3)        any residential tenant who occupied a dwelling unit shall be relocated to a dwelling unit within the building with a floor area equal to not less than 95 percent of the amount of floor area in the dwelling unit previously occupied; and

(4)        as a result of such action by the Chairperson, residential uses will be located on stories above manufacturing uses.

(b)          In M1-6 Districts located within the rectangle formed by West 35th Street, Fifth Avenue, West 40th Street and Sixth Avenue, no dwelling units shall be permitted, except that:

(1)        dwelling units which the Chairperson determines were occupied on May 18, 1981, shall be a permitted use provided that a complete application to permit such use is filed by the owner of the building or the occupant of the dwelling unit not later than June 21, 1983. For the purposes of Article 7C of the New York State Multiple Dwelling Law, such a determination of residential occupancy shall be deemed to permit residential use as-of-right for such dwelling unit.

(2)        in any building for which an alteration application for conversion of floor area used for non-residential use to dwelling units or for an extension or minor enlargement of existing residential use, was filed prior to May 18, 1981, dwelling units shall be permitted, provided that such alterations shall comply with the regulations in effect on the date of such filing.  The right to convert to dwelling units or extend or enlarge existing residential use pursuant to the provisions of this paragraph (b) shall expire one year from July 23, 1981, unless a temporary or permanent certificate of occupancy has been issued.