Follow these simple steps to update Xiaomi Mi3/4 and MiNote from 4.4 to 6.0:
Install MIUI 5.12.17 via Updater app to merge your system partitions if you haven't done so yet (no more dual system support);
Do a full wipe (highly recommended);
Install MIUI 5.12.17 again and do a full wipe once...
