Cal. Pub. Cont. Code § 20451

Written objections to the proposed changes may be filed with the clerk by any interested person at any time not later than the time set for the hearing. The legislative body shall hear and pass upon the objections at the time appointed, or at any time to which the hearing thereof may be adjourned, and its decision thereon shall be final and conclusive. If no written objections to the changes have been delivered to the clerk up to the hour set for hearing thereon, or if the objections have been heard and found by the legislative body to be insufficient or have been overruled or denied, immediately thereupon the legislative body by an affirmative vote of four-fifths of its members shall acquire jurisdiction to order the changes made. If the hearing of objections is not required, pursuant to Section 20449, immediately upon passage of the resolution the legislative body shall acquire jurisdiction to order the changes made. The decisions and determinations of the legislative body ordering the changes shall be final and conclusive upon all persons entitled to appeal thereupon to the legislative body.