Reputedly, Xiaomi remains on target to announce the Xiaomi 12 in December. According to Digital Chat Station, while the Xiaomi 12 is expected to outclass Xiaomi's current premier handset in multiple areas, the MIX 4 will have the edge in others, including an in-display camera.
https://www.notebookcheck.net/Xiaomi-12-remains-on-track-to-launch-in-December-with-some-upgrades-over-the-MIX-4.578720.0.html