This should pre-heat your house, prior to arriving back home if you have previously set it to away while travelling abroad. Geofence could be used with Ecobee 3 and HomeKit, but this is a very specific geofence that is at least far enough away from my own house that it will give the home time to warm up.
Then
Set thermostat comfort profile until next transition
This Action will set the thermostat into a hold using the settings from the specified comfort profile. This comfort profile hold will remain in effect until the next next comfort profile transition in the program.
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