Millenicom Customer Accounts Acquired by Verizon

I understand the double the data for the same price... but that deal is only going to last until sometime in 2015 ( as it stands now) and from what I thought I read from another post... once you double your data you can't go back down to what it was before. So when the deal ends in 2015 you are stuck with the "double data" and you don't know what they are going to charge for it at that point.

Anyone know if I'm wrong on this for sure??