so is this really going to happen?
kinda seems like it's not going to happen.
It's happening, and still on track to begin construction this Spring. Public announcement will be before the end of the year. Changing architects is the biggest reason it isn't public yet... K-State AD can't legally show AECOM any of the old Populous design work, so they have to work through some of the basic things again (what do we want, what are our requirements and so forth).
How much time should the actual construction take?
It depends, are you using the Urick/Weiser construction time frame model? If so, 9 years, construction will take 9 years . . . oh, unless you're going to slap up a half done cookie cutter building, then 9 months.