Cal. Pub. Util. Code § 1701.5

(a) Except as specified in subdivision (b), in a ratesetting or quasi-legislative case, the commission shall resolve the issues raised in the scoping memo within 18 months of the date the scoping memo is issued, unless the commission makes a written determination that the deadline cannot be met, including findings as to the reason, and issues an order extending the deadline. No single order may extend the deadline for more than 60 days.

(b) Notwithstanding subdivision (a), the commission may specify in a scoping memo a resolution date later than 18 months from the date the scoping memo is issued, if that scoping memo includes specific reasons for the necessity of a later date and the commissioner assigned to the case approves the date.