just updated my redmi 3 pro (snap 616, RAM 3GB, ROM 32GB)
Before:
UBL, TWRP 3.0.2 ido, xiaomi.eu v6.9.1, root (super SU2.76)
dirty update:
1. reboot to TWRP
2. backup current ROM (wipe dalvik and cache)
3. Flash rom
4. wipe dalvik and cache
5. reboot to system (aprox. 15 minutes)
all program...