The 60- or 90-day time period specified in § 5.7002 of this title (relating to Cancellations) is calculated from the effective date of the policy to the date on which notice of cancellation is mailed. For the purpose of these sections, a renewal, in the same company, of an expiring policy is considered as an extension of the earlier policy period.
28 Tex. Admin. Code § 5.7003