27 C.F.R. § 24.137
(b) Qualifying documents. Where the proprietor desires to alternate a portion of wine premises for customs use, the following qualifying documents will be filed:
(c) Alternation. After approval of the qualifying documents by the appropriate TTB officer, the proprietor may alternate the wine premises. Portions of the wine premises to be excluded by curtailment or included by extension may not be used for purposes other than those authorized. Prior to the effective date and hour of the alternation, the proprietor shall remove all wine and spirits from the portion of the wine premises to be alternated for customs purposes.
(Sec. 201, Pub. L. 85-859, 72 Stat. 1379, as amended, 1380, as amended, 1381, as amended (26 U.S.C. 5356, 5357, 5361, 5365, 5367))
(Approved by the Office of Management and Budget under control number 1512-0058)
[T.D. ATF-299, 55 FR 24989, June 19, 1990, as amended by T.D. ATF-344, 58 FR 40354, July 28, 1993; T.D. ATF-409, 64 FR 13683, 13685, Mar. 22, 1999; T.D. TTB-196, 89 FR 87941, Nov. 6, 2024]