I think Gypsy will be like the Scheisse of BTWball, the last "official" song. And she'll change the lyrics to say "Paris be my home for today hey" for example.
And then she'll come back with Applause and finish the show.
Aura will most likely start the show, Gypsy will probably be the last on the setlist, Applause being the encore as ivi said. I feel so good today that I know her best era started just two years ago and she gave us her best album, and also her last BTW Ball was a year ago...Time goes by so fast, she healed so quickly to be honest.
Either way, I would love the setlist to be like this: