(a)(1) Except as provided in subdivision (2) of this subsection, where the results of any civil audit, investigation, examination or reexamination conducted by the Commissioner of Revenue Services have become final by operation of law or by exhaustion of all available administrative and judicial rights of appeal, the period covered by such audit, investigation, examination or reexamination shall be closed and the taxpayer may not file any additional claims for refund for such period.
(2) A taxpayer may file a claim of refund for any period for which the results of any civil audit, investigation, examination or reexamination conducted by the commissioner have become final by operation of law or for which the associated administrative or judicial rights of appeal have been exhausted, provided such claim is filed not later than six months after the date such results become final by operation of law or the date such rights of appeal are exhausted, as applicable and whichever is later.
(b) The provisions of subsection (a) of this section shall not affect claims for refunds authorized under the provisions of sections 12-226 , 12-704 and 12-727 .