Cal. Sts. & High. Code § 5824

At any time not later than the hour for hearing objections to the proposed work as provided in this division, or at any time not later than the time fixed in the resolution of intention for the hearing of objections, if the resolution of intention provides for maintenance only, any person permitted by the provisions of this division to make written protest against the proposed work or against the extent of the district to be assessed therefor, or both, may make like protest and in like manner against the ordering of the formation of the maintenance district or against the extent of the maintenance district, or both.