Below, with thermostat in OFF, I set the mode to "Auto Cool/Heat"
The relevant thermostat is "Front Hall".
Sep 17, 2020 at 5:36:22 PM
Ecobee 2 Debug logLevel = 10
Ecobee 2 Debug updateFrequency = 900.0
Ecobee 2 Debug setting temperature scale to C
Ecobee 2 Debug Ecobee Account (1428206274): Ecobee Account Update OK, got info on 2 thermostats
Ecobee 2 Debug Ecobee Account (1428206274): getting data for 'Front Hall', 521703550260
Ecobee 2 Debug Ecobee Account (1428206274): getting data for remote sensor 'North Office', C5SW
Ecobee 2 Debug Ecobee Account (1428206274): getting data for 'Stairs', 521781046633
Ecobee 2 Debug Ecobee Front Hall: Updating device
Ecobee 2 Debug Ecobee Front Hall Remote - North Office: Updating device
Sep 17, 2020 at 5:36:42 PM
Ecobee 2 Debug Ecobee Front Hall: action.thermostatAction: SetHvacMode
Ecobee 2 Debug Ecobee Front Hall (521703550260): Mode set to: auto
Ecobee 2 Debug API 'set HVAC mode' request completed, result = <Response [200]>
Ecobee 2 Debug Ecobee Account (1428206274): Ecobee Account Update OK, got info on 2 thermostats
Ecobee 2 Debug Ecobee Account (1428206274): getting data for 'Front Hall', 521703550260
Ecobee 2 Debug Ecobee Account (1428206274): getting data for remote sensor 'North Office', C5SW
Ecobee 2 Debug Ecobee Account (1428206274): getting data for 'Stairs', 521781046633
Ecobee 2 Debug Ecobee Front Hall: Updating device
Ecobee 2 Debug Ecobee Front Hall Remote - North Office: Updating device