Just before Uncarrier 5.0 was announced, one of our sources got in touch to show us they’d been testing a Galaxy Avant. It seems like an age ago, but it was just last month. One thing the insider didn’t tell us was which bands the Avant was compatible with. However, the FCC filing for that device (pictured above) reveal that it could be one of the first handsets compatible with the 700MHz band 12 LTE T-Mo acquired from Verizon earlier in the year.

As uncovered by Reddit user, danrant, the device with model number SM-G386T is compatible with UMTS bands 850/1700/1900 as well as LTE bands 2,4,5,12. Thus, making it fully T-Mobile friendly.

Now, there’s another rumored upcoming device that could be band 12 compatible, and that’s the Xperia Z3. It’s a device that’s cropped  up a number of times online recently. An FCC filing reveals some details regarding the next generation of Sony’s flagship smartphones. At least, that’s what most tech pundits online are assuming the filing is. Whatever the device is, it’s compatible with band 12, making it another potential handset for T-Mobile to hook up to its low band spectrum when it goes live at the end of this year.

What’s interesting with this Sony filing is the “Test Report Re-Use” which stipulates why Sony has tested the same handset twice under two IDs, and it’s simply that one was band 12 friendly, while the other isn’t (among some other differences).

What’s interesting here is that – so far – T-Mobile has been very quiet on any handsets built to support the 700MHz spectrum bought from VZW. And that’s simply because none of them do yet. Some device do support a 700MHz frequency, but in almost every case, it’s band 17 which isn’t the same flavor as T-Mobile’s. Both these devices – whatever they turn out to be – are compatible with band 12.

Of course, there’s a chance that neither ends up on T-Mo. But given the fact it is already being tested on T-Mobile, we’re pretty sure that the Galaxy Avant is going to be the first 700MHz LTE T-Mobile phone. We have no idea on a release date for the Z3 yet, but, we’ll keep you updated whenever there’s anything new to share.

Source: Reddit 1, &  2, FCC Galaxy Avant, FCC Sony Device