A hot potato: T-Mobile will shut down Sprint's LTE network no later than June 30, 2022, the carrier has confirmed. By that time, T-Mobile will have already retired Sprint's older 3G (CDMA) network as well. How will that impact its agreement with Dish Network?

T-Mobile completed its mega merger with Sprint on April 1, 2020 - the same day that T-Mobile chief John Legere stepped down. In order to achieve regulatory approval, T-Mobile had to agree to multiple concessions that would help Dish Network become the nation's new fourth wireless carrier including offloading Boost Mobile and making spectrum available to Dish Network for a set number of years.

Things started heating up earlier this year when T-Mobile announced plans to shutter Sprint's CDMA network by January 1, 2022. That's a problem for Dish because some of its Boost Mobile customers still use CDMA-based phones and will need to upgrade to newer devices before the cutoff date.

In response, Dish went out and signed a 10-year service agreement with AT&T to provide connectivity to its Boost, Ting and Republic Wireless customers. That deal is worth at least $5 billion, Dish revealed in a filing with the US Securities and Exchange Commission.

Curiously enough, T-Mobile has also said it plans to retire its older GSM 2G and UMTS 3G networks, but no date has been set yet.