12 CFR 210.10 - Time schedule and availability of credits for cash items and returned checks.
(a) Each Reserve Bank shall include in its operating circulars a time schedule for each of its offices indicating when the amount of any cash item or returned check received by it is counted toward the balance maintained to satisfy a reserve balance requirement for purposes of part 204 of this chapter (Regulation D) and becomes available for use by the sender or paying or returning bank. The Reserve Bank that holds the settlement account shall give either immediate or deferred credit to a sender, a paying bank, or a returning bank (other than a foreign correspondent) in accordance with the time schedule of the receiving Reserve Bank. A Reserve Bank ordinarily gives credit to a foreign correspondent only when the Reserve Bank receives payment of the item in actually and finally collected funds, but, in its discretion, a Reserve Bank may give immediate or deferred credit in accordance with its time schedule.
(b) Notwithstanding its time schedule, a Reserve Bank may refuse at any time to permit the use of credit given by it for any cash item or returned check, and may defer availability after credit is received by the Reserve Bank for a period of time that is reasonable under the circumstances.