Xiaomi's poor form with Android One software is well-documented but the latest stunt may be a tough pill for owners of the Mi A3 to swallow. Mi A3 owners across the globe woke up to a new 1.40 GB OTA that appears to have been intended for Mexican models only, and has now disabled dual-SIM functionality on the phones of those unfortunate enough to have installed it.
https://www.notebookcheck.net/The-Mi-A3-receives-a-debilitating-update-Xiaomi-acknowledges-fault.481159.0.html