Although Xiaomi released Android 8.0 Oreo for the Mi A1 handset before the end of 2017 as they previously had promised, the first security patch of the new year arrives with a long delay. Even worse, the new firmware does not bring Android 8.1 or the latest security patch from Google, only packing last month's update and nothing else.
https://www.notebookcheck.net/Last-month-s-security-patch-finally-available-for-the-Xiaomi-Mi-A1-in-Europe.290242.0.html