The MIUI 9 global rollout continues with Xiaomi Mi Max and its India-exclusive variant the Xiaomi Mi Max Prime. The upgrade version is V9.1.1.0.NBCMIEI for the Mi Max and is around 1.5 GB in size. The Prime version should get V9.1.2.0.NBDMIEI but the package is essentially the same. MIUI 9 brings to Xiaomi users new features like Split Screen, Search for Apps, Dual Apps and a new assistant, accessible with a left swipe from the home screen. There are plenty of design customizations and the Indian customers are in for a treat with special holiday cards in the Calendar...
Source: https://www.gsmarena.com/xiaomi_mi_max_mi_max_prime_global_miui_9-news-28626.php