9.5.19 update enables Anti Rollback Protection, ARB = 4 .. so here is the official statement http://en.miui.com/thread-3156438-1-1.html
Global Stable ROM
1. If you are on Stable ROM V 9.5.19 or ROM above, you can flash all Stable ROMs after V 9....
As you all know xiaomi displays ads in download app file manager and sometimes in settings, but there is an option to disable these ads and i have tested this in MIUI10 and i hope it will work for everyone just follow these steps.
10.3.1 Oreo based stable update is rolling out with April security patch
10.2.2 is rolling out with March security patch
Added incremental OTA link in OP
I will add full OTA link later
Edit : Added full OTA link
Checkout these screenshots