CA Educ Code Section 5023

(a)

Whenever an elementary, high school or unified school district or a portion of any such district is annexed to another school district in which trustee areas have been established the county committee on school district organization of the county having jurisdiction over the annexing district shall study and make recommendations with respect to trustee areas of the annexing district as enlarged. Procedures contained in Section 5019 shall be used for purposes of this section.

(b)

Recommendations adopted under provisions of subdivision (a), if approved by the electors, shall become effective on the same date that the annexing district as enlarged becomes effective for all purposes.