I think they went en banc because Kennedy is a certain "dead end".
So much for the law mandating denovo review, the feds have just applied an "abuse of discretion" standard.
They got it. He newly reviewed the legal arguments brought forth in their filing. He found them lacking. The law could have said "shall grant injunctive relief," but they pulled that part from the law.
Now we just wait for the full 11th to prove me wrong (hopefully).