California Code, Elections Code - ELEC § 21140

(a) For redistricting occurring in 2031 and thereafter, the boundaries of the election districts shall be adopted by the districting body not later than 204 days before the local jurisdiction's next regular election occurring after January 1 in each year ending in the number two.

(b) This section does not apply when a legislative body transitions from being elected at-large to elected by districts or from districts.

(c) This section does not apply to a charter city that has adopted a different redistricting deadline by ordinance or in its city charter, provided that, if the county conducts the city's elections, the county is able to administratively accommodate this later deadline. If the county cannot accommodate that deadline, the county shall provide the charter city with the latest deadline the county can reasonably accommodate, which shall be used as the map-adoption deadline for purposes of Section 21180 and which the city shall post to the city's redistricting web page.