Cal. Elec. Code § 10516

(a) Notwithstanding any other provision of law, in any district or agency election, if a declaration of candidacy for an incumbent elective officer of a district is not filed by 5 p.m. on the 88th day before the general district election, or is filed but then is withdrawn before 5 p.m. on the 88th day before the election, any person other than the person who was the incumbent on the 88th day shall have until 5 p.m. on the 83rd day before the election to file a declaration of candidacy for the elective office.

(b) This section is not applicable where there is no incumbent to be elected. If this section is applicable, notwithstanding Section 10510, a candidate may withdraw their declaration of candidacy until 5 p.m. on the 83rd day before the general election.