27 C.F.R. § 19.230
Under certain conditions, the proprietor must prepay the distilled spirits tax required, using TTB F 5000.24, Excise Tax Return, before removing spirits from the bonded premises. Those conditions are:
(c) When the proprietor receives a notice from the appropriate TTB officer that the tax must be prepaid. Such notice may be issued to the proprietor if—
(d) When the proprietor's withdrawal bond, or the withdrawal coverage under its unit bond, is for less than the maximum penal sum. This condition does not apply to a proprietor who is exempt from furnishing a bond under § 19.151(d). The proprietor must prepay the tax to the extent that a withdrawal would cause the outstanding tax liability to exceed the limits of coverage under the bond. See also § 19.231 if the bond is for less than the maximum penal sum.
(26 U.S.C. 5213, 5555)
[T.D. TTB-92, 76 FR 9090, Feb. 16, 2011, as amended by T.D. TTB-146, 82 FR 1122, Jan. 4, 2017]