S&B-64: Suppose a Seller posts additional Performance Assurance so that the Delivery Term will start on May 31, 2022 when the Seller delivers the first REC. If the Project starts generating RECs in March 2022, can we bank the RECs generated between these two dates to use during the Delivery Term when we have a Shortfall Year?

You are incorrectly assuming that if the Seller posts sufficient additional Performance Assurance, then the Seller will have the option to deliver the first REC on May 31, 2022 and this is when the Delivery Term will start. The Delivery Term starts on the date that the first REC is issued by PJM EIS GATS or M-RETS. If the Seller posts sufficient Performance Assurance to satisfy the Increased Collateral Requirement, and the Project becomes operational in March 2022, then the Delivery Term starts once the first REC is issued thereafter. Please see Section 1.22.2 of the Master REC Agreement.