Xiaomi is sending out the November security patch to its lineup and the update has now been received by owners of the Mi Mix 3 5G and Mi A3. For the Mix 3 5G, the update is going out to the European version of the device. For the Mi A3, however, it's been sent out to both the European and Global models.
https://www.notebookcheck.net/New-updates-arrive-for-the-Mi-A3-and-Mi-Mix-3-5G.506624.0.html