S.C. Code Ann. § 38-73-1410

After June 30, 1989, upon the effective date of this section, nothing herein should be construed to require a rating organization or its members or subscribers to immediately refile final rates or premium charges previously approved by the director or his designee for private passenger automobile insurance coverages. Members or subscribers of a rating organization are authorized to continue to use automobile insurance rates or premium charges, approved before the effective date of this section, or decreases from those rates or premium charges filed by the rating organization and, subsequently, approved after the effective date of this section.