N.C. Gen. Stat. § 58-36-45

Whenever an insurer changes the coverage other than at the request of the insured or changes the premium rate, it shall give the insured written notice of such coverage change or premium rate change at least 15 days in advance of the effective date of such change or changes with a copy of such notice to the insurance producer. This section shall apply to all policies and coverages subject to the provisions of this Article except workers' compensation insurance and employers' liability insurance written in connection therewith.