Each person required to maintain records of operations and transactions under this part shall:

(a) Keep on file all records and copies of claims for a period of not less than 3 years following the date of transaction or, at the discretion of the appropriate TTB officer, an additional 3-year period; and

(b) Maintain all records at the permit premises, except that the records may be kept at a central location by a State or political subdivision of a State, or the District of Columbia which distributes tax-free alcohol to multiple dependent agencies, institutions, or departments.