In case the claimant, from causes beyond his control, is unable to furnish the landing certificate or proof of loss, within the time prescribed therefor, he may make an application to the appropriate TTB officer for an extension of time in which to do so. Such application must state specifically the cause of failure to furnish the evidence. Two extensions of three months each may be granted by the appropriate TTB officer, provided the surety on the drawback bond of the claimant assents in writing thereto.
27 C.F.R. § 44.231
72 Stat. 1419; 26 U.S.C. 5706