After sending out updates to the Redmi Note 8 Pro, Redmi Note 9, and Redmi Note 8, Xiaomi is now rolling out new builds to the Poco X3 in multiple regions. The Mi Mix 3 5G is, surprisingly, also getting the December security patch.
https://www.notebookcheck.net/New-updates-arrive-for-the-Mi-Mix-3-5G-and-Poco-X3.512035.0.html