Gov. Code, § 21229

(a) A retired person may serve without reinstatement from retirement or loss or interruption of benefits provided by this system upon appointment by a school employer or by the Trustees of the California State University either during an emergency to prevent stoppage of public business or because the retired person has specialized skills needed in performing work of limited duration. These appointments shall not exceed a combined total of 960 hours for all employers each fiscal year. The compensation for the appointment shall not exceed the maximum monthly base salary paid to other employees performing comparable duties as listed on a publicly available pay schedule divided by 173.333 to equal an hourly rate. A retired person appointed pursuant to this section shall not receive any benefits, incentives, compensation in lieu of benefits, or other forms of compensation in addition to the hourly rate. A retired annuitant appointed pursuant to this section shall not work more than 960 hours each fiscal year regardless of whether he or she works for one or more employers.

(b) (1) This section shall not apply to a retired person otherwise eligible to serve without reinstatement from retirement, if during the 12-month period prior to an appointment described in this section, that retired person receives unemployment insurance compensation arising out of prior employment subject to this section with the same employer.

(2) A retired person who accepts an appointment after receiving unemployment insurance compensation as described in this subdivision shall terminate that employment on the last day of the current pay period and shall not be eligible for reappointment subject to this section for a period of 12 months following the last day of employment. The retired person shall not be subject to Section 21202 or subdivision (b) of Section 21220.