There really is none as a traffic ticket does not expire and is not subject to a statute of limitations. The statute of limitations is to prevent one from being accused of a crime when the witnesses may no longer be available and defense difficult. In this case, you have already been notified of the violation and have not defended against it in the time allotted. A traffic ticket is a notice of violation. Some jurisdictions will stop trying to collect, or declare on amnesty on tickets on a specific time frame.