I just signed up recently and chose a lower plan to see how much data we were actually using and it seems we need the highest plan you offer. when we signed up there were special offers for the first few months. Are they still available after i changed plans?
Since the promotions are discounts, I would expect the discount amount to applied to your new plan for the remainder of your introductory period (or possibly prorated if moving to a lesser plan and a lesser discount amount). You most certainly wouldn't get a totally new promo period. As Bev notes, call and ask for the bottom line should you switch.
Yeah call to find out and change, that way you'll know for sure. When I changed my plan and my 3 months were still there, I didn't get the lower price but maybe things have changed since a year ago! Good luck! Always good to call in to find out, maybe each area is different as the plans are different in every area too!