Cal. Sts. & Hy. Code § 9707
No action or proceeding to set aside, cancel, avoid, annul, or correct any reassessment levied under this division, or to review any of the proceedings, acts, or determinations made in the proceedings for the reassessment and the issuance of refunding bonds, or to question the validity of or enjoin the collection of the reassessment or any of the reassessments therein, or to enjoin the issuance of any bonds to represent reassessments, shall be maintained by any person, nor shall any person urge, plead or prove, the invalidity of any reassessment or any refunding bond in any action, unless the action is commenced within 30 days from the date of adoption of the resolution providing for the issuance of the refunding bonds.
Ca. Sts. and High. Code § 9707