As I recall from looking up the process after another adcom ambush a very long time ago, the sponsor and the panelists receive advance copies of the briefing documents, approximately 1-2 weeks? before they are formally published. My suspicion would be that at least one of the panelists leaked the briefing documents and that led to the massive put. The SEC, of course, should have followed the money and forwarded the information re the guilty parties to the DOJ for prosecution, but we know that’s not how things work in our well-lubricated economy.