T-Mobile is getting busy building out 5G with Sprint's prized 2.5GHz spectrum. The company is working towards transitioning legacy customers over to the new network over the next few years — albeit in an ugly way for some — and that means making sure the new technology's robust enough to be attractive. The bottom line, then, is that we should expect to see 2.5GHz everywhere and soon.

In a presentation with analyst firm MoffettNathanson, T-Mobile President of Technology Neville Ray laid out some of the work being done for 2.5GHz spectrum — said to bring a balance of high throughput and land range versus higher and lower frequencies.

The New T-Mobile started adding 2.5GHz radios to its own towers starting in March after beginning negotiations with local councils and land owners on permits and leases the year before — when the merger with Sprint was still in question. Those dealings paved the way for the company to get a head start on bringing the spectrum online.

"We already have momentum," Ray said, "and we'll be building at a clip of almost a thousand overlays a month as we move into May and June."

In New York City and Philadelphia, where 2.5GHz 5G has just been deployed, the executive claims an eight to ten times improvement on LTE performance at around 35Mbps and a fivefold boost on average performance of 100Mbps.

Ray said T-Mobile is able to boast a sub-6 portfolio around three times the size of Verizon's and twice AT&T's holdings. In Philly alone, T-Mobile has 250% of Big Red's entire millimeter wave footprint.

There's plenty to build on in the 3 years before the company is able to introduce new rate plans — it had pledged to freeze prices as a term of the merger.