Hi, first of all I'm usually updating my phone using TWRP.
Here is my timeline story ;) :
I updated my MiNote Pro from 6.12.22 to 7.2.9, following the instructions posted in 7.2.9 rom:
1) download 7.2.9 rom.
2) install via Updater
3) installation passed, phone was locked, battery drain issue...