Sorry if this has been posted already as I ready the first 5 pages of the thread and then the last two...but I got an email from Disney that says the following:
Today we are excited to share that starting on Monday, April 28, 2014, all Walt Disney World® Resort Guests will be able to make additional FastPass+ selections at in-park kiosks after they have redeemed their original (up to three) selections.
Guests will be able to make one additional selection at a time, based on availability. After they redeem that additional selection, they can go to a FastPass+ kiosk to make another selection, and so on. (The additional FastPass+ selections must be made at a kiosk only.)
Guests will be able to make their additional selection(s) for an experience at which they already redeemed a FastPass+ selection earlier that day.
Guests with valid park-hopping privileges will be able to make their additional selection(s) at another park. Those selections must be made at a kiosk in the park where the desired experience is located.
Key note on the second bullet point...you CAN make a FP+ selection for a ride you already rode with your fourth FP+ choice.