I am wondering if anyone else is having issues with the accuracy of Homekit being able to determine whether you are home or not. If, for example, I set my lights to turn on when I arrive home or turn off when I leave they flick on and off randomly while I am still home. Looking at the maps app often shows my location being more than 250m away from my home even when I am actually at home, so I assume this is the cause.

I am aware that setting up a large geofence would deal with the above example, however I don't think that this would be an effective solution when I am setting up automations that use the 'only when I am home/away' toggle. 

Is this a common problem? I am surprised that this feature appears to be relying on my iPhone GPS given its lack of reliability indoors - I would have thought that it would determine whether or not I am home based on whether my iPhone is connected to my wifi.