N.Y. Comp. Codes R. & Regs. tit. 21, § 459.3 – Prior notice time requirement.

(a) No utility shall discontinue service for failure to pay electric service bills rendered or for failure to post a required deposit until at least 35 days have elapsed from date payment was due. Additionally, such termination cannot occur until:
1. (1) at least 15 days after written notice has been served personally upon a customer or resident 18 years of age or older; or
2. (2) at least 15 days after the utility mails written notice by a registered or certified letter to the customer at the address at which service is received.
(b) If a customer has requested in writing to the utility to have an alternate address for billing purposes, the notice authorized under paragraph (a)(2) of this section shall be sent both to the alternate address and to the premises where service is received.