Update 2 (5/17/19 @ 11:25 AM ET): Xiaomi has now officially released the global beta of MIUI 10 (Android Pie) for the Mi Mix 2.
Update 1 (5/10/19 @ 9:04 PM ET): Just as promised, the Android Pie update for the Xiaomi Mi Mix 2 seems to be in the works. If you're adventurous enough, you can try out the beta by downloading and sideloading the recovery ROM linked below.
Xiaomi has a number of devices on the market right now and many have been wondering if their device will get updated to Android Pie. Xiaomi's updates are a bit different than other OEMs as they have their own ROM (MIUI) that they roll out to devices for years. Most OEMs stop pushing out updates after a couple of years, but Xiaomi maintains multiple builds of MIUI which are based on different versions of Android. So while dozens of their devices are getting updated to MIUI 10, that doesn't mean they're getting the version that is based on Android Pie. However, it has been revealed that both the Xiaomi Mi Note 3 and the Xiaomi Mi Mix 2 are both getting updated to Android Pie in the near future.
We don't have an exact date as to when this update will happen, but a roadmap shows a list of devices and when we can expect them to receive the update. Both the Mi Mix 2 and the Mi Note 3 are said to be scheduled to receive an update to Android 9 Pie sometime during Q2 of this year. This means that the update could begin rolling out to the public as early as next month. It also means that we might not end up seeing it until around June. Another thing to point out is that this is for the Chinese version of MIUI for these two devices.
So, Xiaomi plans to update the two smartphones between April and June of this year, but that will be for their home country first. The amount of time it takes them to release the Global version of the MIUI ROM will depend entirely on the demand from those other markets. However, Mi Note 3 and Mi Mix 2 owners should look forward to a new MIUI update in the future that will be based on Android 9 Pie.
Source: Weibo
Update 1: Android Pie Beta for the Xiaomi Mi Mix 2
Courtesy of XDA Recognized Developer yshalsager, you can now download the first Android 9 Pie beta for the Mi Mix 2. This is a recovery ROM for the MIUI 10 China Developer release, so be warned that it'll only have English and Chinese as languages.
Download MIUI 10 (9.5.9) based on Android Pie for the Xiaomi Mi Mix 2
Update 2: Mi Mix 2 Global Beta
After the China release earlier this month, the MIUI 10 global beta is now available for the Xiaomi Mi Mix 2. This beta comes in at version 9.5.16. Download links for the Recovery ROM and Fastboot ROM are below. Here is the full changelog:
Lockscreen, Status bar, Notification shade
- Fixed: Screen lock prompt wasn't displayed correctly in landscape orientation
- Fixed: Battery icons were displayed incorrectly
- Optimized: In-screen fingerprint scanner's response
Game Speed Booster
- Auto brightness, screenshot gestures, and Reading mode can be turned off automatically when Game Turbo is on.
- You can restrict opening Notification shade while playing games.
Download MIUI 10 (9.5.16) Recovery ROM for the Xiaomi Mi Mix 2 / Download MIUI 10 (9.5.16) Fastboot ROM for the Xiaomi Mi Mix 2
Source: Mi Community