Xiaomi has announced that the MIUI 9 Global Stable ROM for all compatible handsets. The update was rolled out to devices like the Mi 3 and Redmi 1S, which were launched nearly 4 years ago.
The complete list of smartphones that have gotten the update include the Redmi 1S, Redmi 2, Redmi 2 Prime, Redmi 3S, Redmi 3S Prime, Redmi 4A, Redmi 4, Redmi Note 4G, Redmi Note Prime, Redmi Note 3, Redmi Note 4, Redmi Y1, Redmi Y1 Lite, Mi 3, Mi 4, Mi 4i, Mi 5, Mi Max, Mi Max Prime, Mi Max 2, Mi Mix 2.
In the MIUI forums, the links to the changelogs for all devices as well as the Recovery ROMs and Fastboot ROMs are available. .