It's a test right now, but it seems to indicate to me that they are concerned about prebooking availability for those rides. Maybe they are thinking that if you are staying there a week, you would probably spend two days at Epcot to see it all anyway, so if they break those two rides up, no big deal, you just ride the other one the other day.
I agree with you there. I still think they are weighing all of there options yet tho.