Other than in connection with the opportunity to submit comments as provided in Sec. 201.1103, no person shall be granted leave to intervene or to participate or otherwise to appear in any agency proceeding or otherwise to challenge an order of disgorgement or creation of a Fair Fund; or an order approving, approving with modifications, or disapproving a plan of disgorgement or a Fair Fund plan; or any determination relating to a plan based solely upon that person's eligibility or potential eligibility to participate in a fund or based upon any private right of action such person may have against any person who is also a respondent in the proceeding.