If you move quickly, it is available by booking two separate reservations; the 1st night under one reservation and the 2nd and 3rd nights under another reservation. I suggest you do this at the same time - if you have two separate devices -so that you get all three nights.
I am not that familiar with PE bookings, but I believe you are allowed to add an extra night, once you have a confirmation. Perhaps someone more familiar can advise, if needed.
Good luck - it was available using this method, just five minutes ago. BTW, I used Chrome.