N.Y. Comp. Codes R. & Regs. tit. 21, § 1950.8
(b) For the purpose of billing users for the consumption shown by the water meter, the demand charges, and for the delivery of water bills, the following districts shall be established and shall be known as meter districts:
(c) Bills for the consumption of water in the various districts shall become due on the first day of the following months and in accordance with the following schedule:
District 1. January, April, July, October
District 2. February, May, August, November
District 3. March, June, September, December
Nonresident February, May, August, November