Current update 8.9.20 (23/09)
36 new ones were released ROM from Global & CN / Xiaomi.eu Source
UPDATE :
The First Global MIUI 10 with Android 9 Pie for the Mi-8 (Dipper) & Mi-Mix 2S (Polaris) is ready.
You will need to change TWRP Recovery before doing the ROM Flash, and you will find it in the ROM zip in the Recovery folder.
At the moment it will be without OTA Updates as the upgrade application is not compatible with Android 9 and needs to be Fixed.
Keep in mind that from now on all Android 9 ROMs have anti-rollback, which must be enabled by Google.
MIUI V10 Developer ROM
CAUTION !
Because we changed a lot about Android 8+ ROMs
It is a good idea to get a TWRP Backup before the Flash of the new ROM.