I'm thinking that it's the Bespin gown. It does some service to Leia, but I don't think it's a version that would be very well received at wider retail. But it might be a good exclusive.
The Hoth version seems like a solid general release offering. And if they were considering the Bespin escape / Carbon Freeze chamber version of Leia? Having the Hoth version and the Bespin escape version on pegs at the same time might be confusing.
All that being said, I would like to see a Bespin escape Leia in the 6" TBS line. But it might be a good offering in a multi-pack with Chewbacca and a blasted apart version of C-3PO in the cargo net.