T-Mobile has rolled out improved LTE coverage to hundreds of locations across the US over the past two weeks, the company’s chief technology officer Neville Ray tweeted. The new low-band and mid-band sites include high-traffic cities like Chicago, Boston, San Francisco, New York, Dallas, and Washington, DC.

As noted by TmoNews and Android Police, the rollout includes low-band 600MHz and 700MHz and mid-band PCS and AWS coverage. Ray also said that more work on 600MHz coverage for spotty areas would be “coming.” This rollout essentially means T-Mobile is shoring up its low-to-middle band areas to get better overall signals in those places, with the focus on getting existing speeds to be more reliable.

T-Mobile has previously indicated that it plans to launch its 5G network in 30 cities this year, though we’ll have to wait until 2019 before we see phones that support 5G on the T-Mobile network.