This is nothing more than their old promotion
The offer before was to cut your bill in half. Now they add T-Mobile (only after they raise their prices) and limit the 50% current plans offered. On top of that, they are all over the place with this sketchy plan. If they give you 50% off Verizon or AT&T, then you will be subject to overages. With T-Mobile, Unlimited data is not eligible for the promotion. Adding insult to injury, Sprint doesn't even come close to giving their loyal customers a decent offer. T-Mobile may have jacked up it's prices, but they are at least providing their customers with incentives. AT&T and Verizon might be more expensive, but in exchange for reliability. This is nothing more than their old promotion being choked.