Just putting this out there. Make sure to have a backup of the Z-Wave JS addon before updating to 0.8.0.
I updated and my thermostat kept becoming unavailable. My smoke detector was fine though.
Once I reverted back, i had to manually change the temp on the thermostat itself before HA could see it again. But since then hasn’t dropped off.
I know this isn’t super scientific and I know corration is not equal to causation and all that. But suspicious none the less.