2a-If the Admin uploads the OTA update, you can download the file to the phone directly and then do a local update using the update app you also use for OTA updates

I've not received the update yet. Did you notice anything interesting except from useless apps? Security updates maybe?

The MediaTek processor probably also does not help....

OTA worked for me. Not sure what changed though.

Have you also tried the local update? Eg download to phone and then flash? As the PC route does not work, you probably will not have TWRP or anything else preventing it from working...

Many thanks for updating the security level to Feb 2018, much appreciated! OTA opdate worked fine!

@mauron: what kernelversion does your BV6000 show? it should be 13 march 2018.If not, your phone is not updated.
Just flashed my phone; the android safety patch date is still June 2017. Why no focus on security? Is it so hard to include the safety patches in an update?

So no other changes, only the camera button?

I had to replace the battery after a year (was swollen and worn out) and battery connector needed to be re-connected after it fell (normally the screen would have been smashed).

Yes, TWRP and SU still work. Don't know why it took a few flashes though. (Got the android-robot with several times).

Maybe the timing of button pressing is critical; I keep the vol+ pressed and then press the power button which I release when the phone boots while still holding vol+.