Dan:
Well, I guess then it all depends on your definition of "Seasoned".
My on board computer dictionary says under seasoned >verb 3. keep (wood) so as to dry it for use as timber. 4(seasoned) accustomed to particular conditions.
Many years ago when I was in the firewood business we considered wood "seasoned" if it had been cut and split for at least three months, as that was the length of a "season".
Working timbers that dry at the rate of 1" in thickness per year after being milled for three months (a season) would or could be considered working the timber "green".
It's my opinion, that three month old timbers are still green. Only wood that has dried to the core would I consider dry.
Working timbers whether green or "seasoned" one has to anticipate shrinkage, and therefore compensate for it. This is done by hollowing out some of the joinery.
Jack Sobon's book, Build a Classic Timber Frame House shows with pictures how to hollow out a joint in order to compensate for shrinkage. If you don't have this one on your library shelf you could consider getting a copy.
Good luck with your project.
Jim Rogers