§ 12. Uncompleted dwellings. 1. The provisions of this chapter
relating to new multiple dwellings shall not apply to any multiple
dwelling for which plans were on file with the department or a permit to
commence building was issued by the department before July first,
nineteen hundred fifty-two, or to any dwelling the plans for conversion
of which to multiple dwelling occupancy, were on file with the
department or a permit authorizing the commencement of the work of such
conversion was issued by the department before such date, provided,
however, a certificate of occupancy as required by the provisions of
section three hundred two shall be obtained therefor prior to July
first, nineteen hundred fifty-seven.

2. No provisions of any part of this section shall be deemed to
prohibit the amendment of any plans filed and approved before July
first, nineteen hundred fifty-two, if such amendment would have been
lawful before such date, or if such amendment complies with the
requirements of this chapter for alterations to buildings of like kind
existing before such date.