A.R.S. § 28-4081

If an insurance carrier has certified a motor vehicle liability policy under section 28-4077 or 28-4078, the insurance carrier shall not cancel or terminate the certified insurance until at least ten days after the insurance carrier files a notice of cancellation or termination of the insurance with the director, except that a policy subsequently procured and certified terminates, on the effective date of its certification, the insurance previously certified with respect to a motor vehicle designated in both certificates.