Cal. Sts. & High. Code § 867

Any owner of property abutting on any highway, the boundary of which is so proposed to be established, who disputes the correctness of the highway boundary claimed and so proposed to be established, must file his written objection at the place specified in said notice within six months of the date of publication of notice, specifying in what respect and to what extent the proposed boundary, as it affects his property, is erroneous.