27 C.F.R. § 19.147
If the proprietor plans to permanently discontinue one or more of the operations listed on the notice of registration filed under subpart D of this part, the proprietor must notify the appropriate TTB officer by filing form TTB F 5110.41, Registration of Distilled Spirits Plant, to show discontinuance of operations. The proprietor must submit the following with TTB F 5110.41:
(c) A written statement indicating whether or not—
(d) A final monthly operations report, as provided for under § 19.632, for each discontinued operation, with each report marked “Final Report.”
(26 U.S.C. 5172, 5271)