Bearing in mind where Ascent plan to base BFJT the fact that I alluded to earlier may have played a major part in the decision making process. Unless we just made it a May-Nov operation?!
Also the Tucanos as they currently are can hardly be said to be a 21st century training platform. They would need at least a cockpit upgrade to look the part. I'm not saying the T6 is exactly an X-Wing fighter but it is at least a little more modern. Whether the planned quantity will be enough remains to be seen!
BV