I mean, if we've learned anything from Brandon, it's that so much of what we are told comes with an asterisk *.
We are made to assume that Rayse is the big bad for 4 books. Even near the very end of Book 4, all things seem to be locked in stone between Dalinar and Rayse for the battle of champions, then BAM, Taravangian. Everything we know has changed.
So just because we are told "ten days" does NOT mean we will get a book that covers just over 10 days. Anything can happen that again, changes everything.
For all we know, its possible to create a second deal that modifies the first. Or changing ownership of Odium messes with the deal itself.
I just find it very difficult to believe that 100% that 5th book is told over just ten days. But this is Brandon, and crazier things have happened.
