1. (a) In the case of a short taxable year of more than five months, the declaration of estimated tax must be filed when the requirements for filing a declaration (see section 22-2.1 of this Subpart) are first met:

   1. (1) before the first day of the sixth month of the current taxable year, then the declaration must be filed on or before the 15th day of the sixth month;
   2. (2) after the last day of the fifth month of the current taxable year but before the first day of the ninth month, then the declaration must be filed on or before the 15th day of the ninth month or the 15th day of the last month of the current taxable year, whichever comes first;
   3. (3) after the last day of the eighth month of the current taxable year, the declaration must be filed on or before the 15th day of the last month of the current taxable year.

Tax Law, § 1460(g)