When a proprietor receives a notice of allowance of credit from TTB, including notification of credit for tax on spirits exported with benefit of drawback as provided in part 28 of this chapter, the proprietor will make an adjusting entry and an explanatory statement on its next excise tax return. The proprietor will identify the notification of allowance of credit that authorizes the adjusting entry in the explanatory statement. If the allowable tax credit is greater than the tax due on the excise tax return, the proprietor will apply the balance of the tax credit to one or more following tax returns until the tax credit is exhausted.