I use the same as beginning... From Mr Tomatico... And i upgrade from 6 > 7 (need reflash MIUI 9 because i don't have access to network) but works now like a charm !!!
If TWRP is already installed > flash new recorery.zip with TWRP.
If not, install TWRP via Fastboot mode and code: 'fastboot flash recovery twrp.img'
Then code 'fastboot boot twrp.img' to boot TWRP.
If TWRP is already installed > flash new recorery.zip with TWRP.
If not, install TWRP via Fastboot mode and code: 'fastboot flash recovery twrp.img'
Then code 'fastboot boot twrp.img' to boot TWRP.