Cal. Gov't Code § 22960.99
(a) The plan’s obligations to a participant, beneficiary, or nonparticipant spouse who has applied for a lump-sum benefit cease upon distribution of the lump-sum benefit.
(b) The plan’s obligations to a participant, beneficiary, or nonparticipant spouse who elected to receive a benefit in the form of installment payments or an annuity cease upon distribution of the final payment.