Judge Sullivan was made a respondent to the mandamus petition by Flynn.
He requested the en banc review.
Long time, no see.
Sullivan was supposed to be a neutral umpire in the case, but he inserted himself as an advocate. Contrary to law he usurped the role of the Executive Branch role as prosecutor where he had no business.
For the Appellate Court, after-the-fact, (that is after Sullivan reached beyond his impartial arbiter role) to address him as respondent, did not change his status, as if the 11-judge panel had granted him standing he previously did not have.
Standing is not determined by filings, though court appellations are.