41 C.F.R. § 101-28.202-4
Reimbursement for services rendered shall be made promptly after receipt of billing. The frequency for billing and reimbursement shall be established by the activity providing warehousing and storage services; however, billing and reimbursement shall be made not less frequently than quarterly nor more frequently than monthly.
[42 FR 2317, Jan. 11, 1977]