40 ILCS 5/8-127: Time of fixing annuities-Waiver.

No annuity or disability benefit shall be fixed, granted or paid under this Article before the effective date.

Any retired employee or widow annuitant may execute a waiver of his or her right to receive all or part of the total annuity. A waiver shall take effect upon its being filed with the board, and may not be revoked after it is executed and filed, except within the first 30 days after being filed.