EPA finalized the disapproval of 21 states’ good neighbor SIP submissions in a rule published on February 13, 2023 (88 FR 9336). EPA subsequently signed final action of the Good Neighbor Plan Rule on March 15, 2023, establishing EGU and non-EGU FIP obligations for sources in 23 states, including the states included in the February SIP disapproval action. Petitioners filed motions to stay EPA’s disapproval action with respect to certain states. The United States Court of Appeals Circuit Courts granted motions to stay EPA’s disapproval of SIP submissions for certain states, causing EPA to lack the authority to implement the March 2023 rule for sources in those states. Applicants then filed for an emergency stay of the Good Neighbor Plan Rule, claiming that EPA failed to anticipate certain states dropping out of the Rule or explain how the Rule could continue to function as a result (i.e., the severability of the Rule). The Court granted the applications to stay enforcement of the rule on this basis. In this action, the EPA is remediating the deficiency identified by the Court by responding to comments related to the issue of severability.