T-Mobile introduced Licensed Assisted Access (LAA) as part of its LTE Advanced Pro network upgrades in the previous quarter, and is already picking the fruits of those labors, it seems. LAA uses carrier aggregation to bind together unlicensed 5GHz spectrum with LTE in the licensed band, enlarging the data pipe significantly.
Verizon and AT&T are also stepping up their LAA efforts, and plan to roll out the expanded network capability in more markets across the US, if the demand warrants it. T-Mobile has been working hard in places like New York and others to upgrade small cells, and install new modular solutions.
Those efforts didn't go unnoticed, apparently, as per CTO Neville Ray in the tweet above - the average speeds of T-Mobile's network in those places has obviously increased 5-10 times, which is a whopping boost for a humble upgrade undertaking.