(a) Where a state or federal court has made a final determination that a provision of this title, as applied by the Commissioner of Revenue Services, violates the Constitution of Connecticut or the United States or other state or federal law and the determination can be applied to past income years, the commissioner may in his discretion provide refunds of taxes by any one or more of the following methods: (1) Lump sum payment within one year of such final determination; (2) periodic equal installments; or (3) credits for any liability of the taxpayer for the same tax in future income years. Installment payments or credits shall be paid in full no later than five years from the date of the final determination of the commissioner or a court of competent jurisdiction that a refund is owed to the taxpayer. Interest at the statutory rate set forth in § 12-227 shall be added to any outstanding balance of the refund due a taxpayer.

(b) The issuance of such refunds or credits shall constitute complete and final settlement of the claim or claims on which the refund was based.

(c) Notwithstanding the provisions of chapter 54, the Commissioner of Revenue Services may, in any instance in which, in accordance with said chapter 54, he may or is required to adopt regulations, adopt rules and issue rulings in lieu of such regulations for the purposes of this section on a temporary basis, which shall have the force and effect of regulations, until such regulations are adopted and approved.