T-Mobile has a helluva great trade-in program that gives you up to $500 when you purchase an iPhone 12 or 12 Pro. Even my old 1st gen SE gets me $215. Plus, they give you an extra $200 if you've been with them for at least 5 years. The trade-in credit is applied over 30 months and they state very clearly that if you drop your line you're on the hook for the credits. The only thing I'm not clear on is if you buy a 12 and pay full price then sell the phone in a year or two. I would imagine they'd still keep applying the credits but it's not clear. Any thoughts on this?