Section 12 - Uncompleted dwellings1. 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.N.Y. Mult. Resid. Law § 12