I’d like to hear about this as well. I just read that my Nest Protects will not trigger allow AutoAway to trigger due to my dogs so I disabled the sensor for my protects. I haven’t had Autoaway trigger once by itself so I look forward to this feature working.
I’ve never had my Nest sense presence well due to it being located in our dining room. ST knows for sure whether you’re present or not using presence tags or your smartphone. I have a SmartApp set up to set the Nest to Away for certain Hello Home actions and set to present for others. I also have another SmartApp that changes the Nest from Heat to Auto to Cool based on the outside temperature measured by my Netatmo sensor.
Nest is good by itself, but great when integrated with ST.