N.Y. Lab. Law § 860-d

§ 860-d. Extension of mass layoff period. A mass layoff of more than\nsix months which, at its outset, was announced to be a mass layoff of\nsix months or less shall be treated as an employment loss under this\narticle unless:\n 1. the extension beyond six months is caused by business circumstances\n(including unforeseeable changes in price or cost) not reasonably\nforeseeable at the time of the initial mass layoff; and\n 2. notice is given at the time it becomes reasonably foreseeable that\nthe extension beyond six months will be required.\n