The Mi Band 7 is around the corner, but it will be compatible with Zepp OS, not Xiaomi's smartwatch platform. It appears that Xiaomi has equipped the next Mi Band with a larger display too, among other changes.
https://www.notebookcheck.net/Xiaomi-Mi-Band-7-leak-points-to-a-larger-display-and-even-GPS-support-for-this-year-s-fitness-tracker.606168.0.html