N.Y. Real Prop. Tax Law § 1622

§ 1622. Dissolution of consolidated assessing unit. 1. Any constituent\nmunicipality may withdraw from the consolidated assessing unit by local\nlaw, provided that such withdrawal shall be effective no sooner than one\nyear after the date on which such local law shall have been filed with\nthe department of state.\n 2. Upon the adoption of a local law of withdrawal by any constituent\nmunicipality, the consolidated assessing unit shall be dissolved sixty\ndays after the filing and completion of the next ensuing final\nassessment roll. In order for the remaining cities and towns to remain\neligible for the benefits of this article thereafter, a new consolidated\nassessing unit must be created in the manner prescribed by this article.\n