N.Y. Comp. Codes R. & Regs. tit. 2, § 349.2 – Eligibility.

(a) For the purpose of determining eligibility, periods during which an employee is on authorized leave of absence without pay shall be counted as State service, not exceeding a total of three months in any one calendar year and not exceeding three months in any one continuous period of such absence.
(b) For the purpose of determining eligibility for an employee who dies while on authorized leave of absence without pay, a previous reinstatement into State service following resignation shall be deemed to have been a new entry into State service.
(c) For the purpose of determining eligibility, a legislative session or a seasonal employee who serves in a position where the service is not continuous throughout the year but recurs or is expected to recur in each successive year in essentially the same form, shall be deemed to be on authorized leave of absence without pay during the period between successive annual periods of service.
(d) For the purpose of determining eligibility under section 657 of the Retirement and Social Security Law, an employee who is suspended or laid off because of the abolition of State positions or curtailment of State activities shall, for a period not exceeding one year following such suspension or layoff, be deemed to be on authorized leave of absence.
(e) An employee who retires from State service while off the payroll on authorized leave of absence is deemed to be in State service upon such retirement.
(f) An employee who resigns or otherwise terminates State service while off the payroll on authorized leave of absence is deemed to have terminated State service on the actual effective date of such termination and is deemed to be in State service upon such actual effective date of such termination.
(g) The effective date of retirement for an employee who, pursuant to section 3 of chapter 980 of the Laws of 1962, elected to remain in the retirement program provided by the University of Buffalo and for an employee who is a member of the optional retirement program provided by article 8-B of the Education Law shall be the day following the last day on which such employee is in the service of State University provided that:
1. (1) prior to such date he has made application under either such retirement programs for a retirement allowance based, in whole or in part, on contributions made on his behalf by State University immediately preceding such date or immediately preceding his last day on the payroll if he makes such application while on leave of absence without pay from the State University;
2. (2) he receives such retirement allowance within 90 days from such date; provided, however, that the President of the State Civil Service Commission may waive such 90-day requirement for good cause shown, and shall waive such requirement if the employee dies within such 90-day period; and
3. (3) if he is, pursuant to subdivision 3 of section 393 of the Education Law, a discontinued service member of the New York State Employees' Retirement System or the New York State Teachers' Retirement System, his effective date of retirement shall be his effective date of retirement from either such system.
(h) An employee compensated on the basis of an annual salary paid over a period of less than 12 months is considered as actively on the payroll during the period covered by payment of that annual salary.