N.Y. Correct. Law § 74

§ 74. Discharge on holidays, Saturdays and Sundays. Where the date of\nrelease on parole or conditional release, or where the date of discharge\nfrom the care or custody of the department, falls on Saturday or Sunday,\nit shall be deemed to fall on the preceding Friday. Where the date of\nsuch release or discharge falls on a legal holiday it shall be deemed to\nfall on the preceding day, except that when such legal holiday falls on\na Monday the date of release shall be deemed to fall on the preceding\nFriday.\n