I have personally tried a Jolla phone on US T-Mobile and confirm 2G only. As we have rehashed over and over you can only get 2G in the US with that phone. Yes N9 had a pentaband that got 3g any country I went. Yes N900 worked on T-mobile US at 3G but no go on Jolla. You will have to bug Jolla about that for their next phone please vote here https://together.jolla.com/question/...jolla-handset/

In Jolla's defence universal LTE modems were not readily available when they were designing the first phone.