A first real image of the upcoming Xiaomi Mi Band 6 has been spotted in EU Declaration of Conformity documents filed by Huami. Although the product is simply listed as a "Smart Band", the model name and live image reveal the wearable as the Mi Band 6. Unfortunately, the photograph included in the filing only shows the band from the side.
https://www.notebookcheck.net/First-Xiaomi-Mi-Band-6-live-image-reveals-a-Mi-Band-5-lookalike-accompanied-by-magnetic-charging-cable.528531.0.html
People want longer battery life. 20 days is way too short. Make it one month or more. Go to work, make a step up, make people life's easier, not just money.