29:30m) I think I can take a shot at guess it:
What we know so far is:
1. FC want to step back from eastern theme (Khitai and Turan),
2. The new zone is bordering with existing zones,
3. It's ancient, buried (??) and mysterious
4. Some Lovecraft tie-ins.
Seems like Hyperborea fits this description perfectly.
1. It is definitely not eastern themed place. Especially with large parts of it's territory being called the Northlands.
2. This zone is indeed bordering with Cimmeria and Turan,
3. It is an ancient kingdom, very advanced in magic. I am sure with country that old there is plenty stuff that got buried and is waiting to be discovered.
4. H. P. Lovecraft used Hyperborea in his Cthulhu Mythos for his version of Atlantis. So says the wikipedia.
Furthermore Hyperborea has been magnificently portrayed in "The Gates of paradise" by Dark Horse comics. So there is plenty of material to draw inspiration from.
If it's true then I am very excited for new adventure pack since Hyperborea was on my list of places I would like to see in game.