Whenever a manufacturer of tobacco products makes a physical inventory of packaged tobacco productsin bond, either as part of normal operations or when required by an appropriate TTB officer, and such inventory discloses a shortage or overage in such products by kind as recorded and reported (i.e.,small cigars, large cigars, chewing tobacco, snuff, pipe tobacco, or roll-your-own tobacco), the manufacturer shall enter such shortage or overage in the records required by § 40.183. Shortages or overages in inventories made at different times may not be used to offset each other, but shall be recorded and reported separately. Unless the manufacturer establishes that a shortage was not caused by a removal subject to the tax the manufacturer shall determine the tax on any shortage, make an adjustment in Schedule A of his next semimonthly tax return and pay the tax thereon. If, after paying the tax on a shortage, the manufacturer satisfactorily establishes that the shortage was not caused by a removal subject to tax, then such payment would be an overpayment of tax which the manufacturer may recover as provided in § 40.286. Where the manufacturer can establish prior to paying the tax on a shortage, that the shortage was not the result of a removal subject to tax he shall submit an explanation of such shortage with his report for the month in which the shortage was disclosed and, if appropriate, he may file claim for remission of tax liability as provided in § 40.287. When an overage is disclosed which the manufacturer can explain, he shall include such explanation in his monthly report and refund of any overpayment may be recovered as provided in § 40.286. Whenever a physical inventory discloses a shortage or overage of tobacco products which have not been packaged the manufacturer shall appropriately enter such shortage or overage in his records and shall, at the time required by the appropriate TTB officer, furnish an explanation in the form of a claim for remission of tax liability as provided in § 40.287. The manufacturer shall pay the tax on any shortage or portion thereof for which he is unable to furnish an explanation acceptable to the appropriate TTB officer.