I believe this question has already been answered for you. I want to clarify my previous answers to ensure that you are aware that if you ignore the Notice of Violation, you can potentially (unlikely, but it's possible) end up with a suspended license AND if they pursue other means of service of process on you, you're on the hook for the cost of that service.
However, you may be right that they missed their deadline. Rule 42 of the AZ Rules of Procedure for Civil Traffic Cases states: "A Notice of Violation is void if its delivery is not initiated . . . within 10 days of the date of violation." So you are correct about the rule's language.
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