California Code, Vehicle Code - VEH § 40260

(a) If the payment of the toll evasion penalty is not received by the person authorized to receive a deposit of the toll evasion penalty by the time and date fixed for appearance on the notice of toll evasion violation under Section 40254, the processing agency shall serve or mail to the registered owner a notice of delinquent toll evasion violation.

(b) Delivery of a notice of delinquent toll evasion violation under this section may be made by personal service or by first-class mail addressed to the registered owner.