An Amazfit Band 6 device has been spotted getting its FCC certification, which is something of a surprise considering the Amazfit Band 5 from Huami only recently went by the same agency too. It could be possible that "Amazfit Band 6" might be the US market name for the widely rumored Xiaomi Mi Smart Band 5 Pro wearable.
https://www.notebookcheck.net/Huami-Amazfit-Band-6-or-Xiaomi-Mi-Smart-Band-5-Pro-Former-visits-the-FCC-suggesting-it-could-be-the-latter-rebranded-for-the-US-market.481546.0.html