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I apologize for cross posting. I tried to ask this at the end of a "solved" discussion. 
 

That said, we signed up with T-Mobile in October of 2021 using the Magenta Max 55+ plan and financed 2 iPhone 13s using the Forever Upgrade with 30 payments. We paid off the phones in March. We got the text in December saying Forever Upgrade was ending but we could keep our plan and get the new Go5G Next benefits keeping our costs the same. We stopped by T-Mobile on Friday and they told us our iPhone 13s were only worth 340.00 on a trade, but if we upgrade to the new plan we could get 830.00 for the phones and it would only cost us another 26.00 a month. We don't want to loose our Magenta Max55+ plan, but also feel like the Forever Upgrade was a bait and switch if our phones are now worth less than half of what we were promised. 
 

At this point is it better to wait for the iPhone 16 and take the 340.00 trade in then? Or, was the salesperson lying to us in order to try to move us to a higher cost plan. He had our account open on his tablet but just kept saying that plans changed and moving was the only way to get the full 830.00 for our devices.