Hold down the power button with ten seconds.

This boots/reboots the BV6000 in 'normal' mode.
The problem is that the recovery.img is broken after the OTA updates from October (201610xx, 20161025). These OTA updates do not have an updated stock recovery.img whereas the updated system itself uses since then updated signing keys (release keys instead of test keys) and ?more?.
And this is the reason why we see the dead android with 'no command'.
To get a working stock recovery.img again - Blackview has to release a new recovery.img