California Code, Education Code - EDC § 89542

(a) If a petition to set aside the resignation of any employee is filed with the State Personnel Board within 30 days after the last date upon which services to the state university or college are rendered, or the date the resignation is tendered, whichever is later, the resignation may be set aside on the ground that it was given or obtained pursuant to or by reason of mistake, fraud, duress, undue influence, or that for any other reason it was not the free, voluntary, and binding act of the person resigning.  The State Personnel Board shall hold a hearing and render a decision on the petition following the same procedure as in the state civil service procedures governing resignations from the state civil service.

(b) If the provisions of this section are in conflict with the provisions of a memorandum of understanding reached pursuant to Chapter 12 (commencing with Section 3560) of Division 4 of Title 1 of the Government Code, the memorandum of understanding shall be controlling without further legislative action, except that if such provisions of a memorandum of understanding require the expenditure of funds, the provisions shall not become effective unless approved by the Legislature in the annual Budget Act.