As you guys might be aware that a developer from Xiaomi, named Ivan has worked hard to create an AOSP ROM for Mi3 currently on Android 4.4.4 Kitkat and now courtesy of him that Mi3 will receive Android Lollipop 5.0 in just matter of few days.
Ivan has complete access to source and has sufficient skill to create a ROM as he is the one behind Official AOSP ROM for several Xiaomi devices including Mi3, Mi2, Mi2S and Mi4. The ROM is currently in development but knowing Ivan Mi3 Android Lollipop 5.0 update will not take more than 2-weeks from today.
The Android Lollipop build will be completely based on Stock Android and will feature few customization that Ivan prefers like Double tap on status bar to sleep etc. Once the ROM is complete we will surely bring the download links as well as a complete guide on how to install latest Android on your Mi3.
Mi4 will also be able to run Android Lollipop 5.0 as both Mi3 and Mi4 runs on same ROM and there shouldn’t be an issue. The ROM will also feature OTA updates and generally get updated in couple of weeks with bug fixes and enhancement in performance.
Source: Weibo Chinese