40 CFR 1039.715 - How do I bank emission credits?
(b) You may designate any emission credits you plan to bank in the reports you submit under § 1039.730 as reserved credits. During the model year and before the due date for the final report, you may designate your reserved emission credits for averaging or trading.
(c) Reserved credits become actual emission credits when you submit your final report. However, we may revoke these emission credits if we are unable to verify them after reviewing your reports or auditing your records.