Cal. Gov't Code § 84202.3

(a) In addition to the campaign reports required by Section 84200, committees pursuant to subdivision (a) of Section 82013 that are primarily formed to support or oppose the qualification, passage, or defeat of a measure and proponents of a state ballot measure who control a committee formed or existing primarily to support the qualification, passage, or defeat of a state ballot measure, shall file campaign reports on the following dates:
1. (1) No later than April 30 for the period January 1 through March 31.
2. (2) No later than October 31 for the period July 1 through September 30.
(b) This section does not apply to a committee during any semiannual period in which the committee is required to file preelection reports pursuant to paragraph (1), (2), or (3) of subdivision (a) of Section 84200.5.
(c) This section does not apply to a committee following the election at which the measure is voted upon unless the committee makes contributions or expenditures to support or oppose the qualification or passage of another ballot measure.