I think Duren will be with the Pistons for the most part.
With the team, learning their schemes, practicing with them, and probably not getting a whole lot of playing time. And there isn't a whole lot of practice time when the season starts either.
Which means when there's a chance to send him to the MCC, they will. WAG is 12-to-15 games starting for the MCC when the opportunity arises, in the first half of the NBA season. Otherwise, he's with the team... travelling with them and everything.
Just my opinion.
About halfway into the season, or maybe even earlier... his playing time (with the Pistons) will start moving up and he won't be sent out anymore... after earning his regular rotation time. Just a guess...