Starting next month, Xiaomi is bringing Android 9.0 Pie to four Mi TV devices. The TVs, which launched running Android 8.1 Oreo, will be updated in batches with a wider roll-out planned a few months later. Xiaomi also told XDA Developers that these updates represent it trying to set a standard for how frequently and quickly Android TVs receive OS upgrades.
https://www.notebookcheck.net/Xiaomi-is-attempting-to-become-the-standard-bearer-of-Android-TV-with-Android-Pie-updates-for-several-Mi-TVs.432969.0.html