I have discovered a software bug in the Android Nest app.
When looking at the thermostat/heating history, I noticed that there were several instances where my status was set from Home to Away by a user who used to be linked the account but now is not. Specifically the event read "Eco temperature set because house was set to Away by Xxxx" where Xxxx is a former user no longer on the account.
The "Switched to Away" events were actually caused by the thermostat's inactivity sensors.
I have turned off all features which can set the house to away except the inactivity sensors, and then turned on the inactivity sensors for one day at a time. Every single day I have used the inactivity sensors I have got a notification linked to this former user, tested on 5 separate says over the course of two months. The notification has never appeared on a day when I didn't have the inactivity sensors set to be able to switch the house to away.
Customer service advice was that my account had been accessed without authorisation (clearly incorrect as in such an instance my own user name would have appeared in the notifications). However, I did update my password anyway and the notifications were still appearing, whenever activity sensors were permitted to set the house to away.
Not a huge problem, posting as I could find no other way to submit bug reports
