No, the Boron LTE is LTE-M1 only for now through AT&T, even though the hardware supports LTE M1/NB1 (edit). That being said, general LTE coverage should already cover more of the country than 2G/3G coverage in the US, which means that you should have LTE-M1 nearly everywhere you have 2G/3G coverage.
As of today, the official quote from our LTE-M1 provider about coverage in the US is the following:
"98% of LTE populations are LTE-M1 capable and within a few months it will be at 100%."