CA Gov't Code Section 75570

(a)

In lieu of the retirement allowance under subdivision (d) of Section 75522 for his or her life alone, a judge who elects to retire with a monthly allowance under subdivision (d) of Section 75522 may elect, or revoke or change a previous election prior to the approval of the previous election, to have the actuarial equivalent of his or her retirement allowance as of the date of retirement applied to a lesser retirement allowance, in accordance with one of the optional settlements specified in Section 75571.

(b)

That election, revocation, or change of election shall be made by a writing filed with the system within 30 calendar days after the making of the first payment on account of any retirement allowance.