T-Mobile is not alone in that deceptive practice. Verizon essentially did the same thing to me when they said we were grandfathered for a $25 "lifetime plan" with unlimited data from the mid 2000's. About 10 years later, they "discontinued" the plan and notified subscribers that it was within their rights to do so. Their prerogative to discontinue a plan is in the fine print of every provider's service contract.Yeah they hosed my parents on their contracted price. Their promises don't mean squat. My parents signed up five years ago and were told their bill was locked in for two lines at $40/month as long as they paid on time. A year ago they were given a notice that T Mobile was changing their plan. My dad brought it up and the representative told them that wasn't a real plan and that the price would go up. They dumped T Mobile.
So something advertised as a "lifetime" guarantee means nothing in the business world, except perhaps for Snap-On and Craftsman hand tools...at least for now.