If a taxpayer through error has filed a return and paid special tax for an incorrect period of liability or for an incorrect class of business, the taxpayer must prepare a corrected TTB Form 5630.5t, designated “Amended Return,” for each tax year involved and must submit the amended return, or returns, with remittance for the total applicable tax and additions to the tax (delinquency penalties and interest), to TTB in accordance with the instructions on the Form 5630.5t or, if the error is discovered by a TTB officer inspecting the premises, to that officer. Subject to the limitations imposed by 26 U.S.C. 6511, the incorrectly paid tax (including additions thereto) may be allowed as a credit against the correct tax (including any additions thereto), as provided in § 46.132, on surrender of the incorrect stamp or stamps, with the amended return or returns noted to show that credit is requested. Any incorrectly paid tax (including additions thereto) that is not credited as provided in § 46.132, including any creditable tax and additions thereto in excess of the correct tax (including additions thereto), may be refunded pursuant to §§ 46.136 through 46.138 if the taxpayer files a corrected return on Form 5630.5t with remittance of the correct amount of tax (including any additions thereto). A new stamp will be issued only for a current period of liability.

(26 U.S.C. 6011)