I suppose, the underlying action being a stay, the case is active in that venue. I would expect the administration to attempt to moot the case somehow, much as GWB mooted one of the terrorist incarceration cases by moving a prisoner into a venue and accepting "regular" criminal jurisdiction. IIRC, that particular accused was a US citizen, and the administration really didn't want an adverse ruling from the court.
Same sort of pressure here. The administration (and probably Congress) want to avoid a ruling that puts pressure on the usual go-along, get-along, wink and a nod system. Nobody wants the immigration law enforced, but Obama went too far.
See if this post will help: http://www.freerepublic.com/focus/f-news/3378198/posts
I wonder if the 4 envelopes correspond to the 4 issues, as listed on ScotusBlog:
Issue:
(1) Whether a state that voluntarily provides a subsidy to all aliens with deferred action has Article III standing and a justiciable cause of action under the Administrative Procedure Act (APA) to challenge the Secretary of Homeland Security’s guidance seeking to establish a process for considering deferred action for certain aliens because it will lead to more aliens having deferred action;
(2) whether the guidance is arbitrary and capricious or otherwise not in accordance with law;
(3) whether the guidance was subject to the APA’s notice-and-comment procedures; and
(4) whether the guidance violates the Take Care Clause of the Constitution, Article II, section 3.