Since its early days as a mobile service provider, T-Mobile has branded itself as an “un-carrier.” The company worked hard to differentiate itself from its competitors, promising customers more flexibility when it comes to everything from add-ons to phone plans. Now that it’s joined the rankings of large service providers, however, T-Mobile seems to be changing its tune. Leaked documents circulating online suggest that the company is planning to force its new plan tier on existing customers, which could amount to costlier monthly bills.

The documents originally posted on Reddit by u/Appropriate_Draft_77 suggest that, starting on October 17, T-Mobile will begin notifying existing customers of plan changes. Those who have a Magenta or ONE Plan will be moved to a Go5G plan, while Magenta 55+ plan owners will be migrated to a Go5G 55+ plan. Customers who have a Simple Choice plan will either be shifted to a Magenta or Essentials Select plan. Finally, Simple Choice Business plan members will be migrated to a Business Unlimited Advanced plan. For the time being, customers will be able to opt out of the changes, but it’s unclear if this will be the case in the future (via The Mobile Report).

Depending on your plan type, you can see a monthly bill increase of up to $10 per line. The leaked documents also appear to show some of the offers T-Mobile will throw in if you opt out. For instance, a customer with one or two T-Mobile lines could be offered a $10 “adjustment.” Customers who opt out with a plan consisting of three lines or more might be offered $25. T-Mobile representatives also appear to be being prepped with lines to feed customers who ask to opt out as well. Generally speaking, these cost increases will likely be addressed as “different costs” instead, and reps will be ready to talk customers into the Go5G plans.

T-Mobile just launched this new tier of plans in August 2023, packed with incentives to entice new customers — but it didn’t offer much to existing ones. Perhaps the biggest advantage to a new Go5 plan is the option to upgrade your phone within six months, assuming you’ve paid off at least half of it. However, this doesn’t do much for customers who have already fully purchased their phone or have a cheaper existing T-Mobile plan.

While these leaked documents only do so much to lessen the financial blow that seems to be looming, don’t underestimate your power to opt out. Even if you’ll only be temporarily avoiding a price hike, it’ll buy you time to shop around for another mobile service provider. If you’re a fan of T-Mobile’s network, a good place to start looking might be Google Fi, which uses the magenta carrier’s network and has several low-cost plan options.