Hi @rey_rios, you’d be able to do this using this smartapp:
The only drawback is that you would then rely on ST scheduling only (not ecobee’s scheduling), which is starting
to be better (as ST is implementing a new scheduler), but it’s not as reliable as ecobee.
I tried to work around the ST scheduling issue as much as I could, and I think the smartapp is quite reliable now.
This smartapp has been designed for controlling the temp and fan settings based on rooms, zones, and schedules that you configure for your home. You can run the schedules only when one or some ST hello homes are set (can also be custom ones). An outdoor temp sensor can be used to trigger more heating/cooling or a specific fan mode, or even to switch the thermostat mode (heat, cool, auto).
The smartapp setup (i.e. rooms, zones, schedules) takes a little bit more time than a regular smartapp, but if you plan to add smart vents later, this smartapp can grow with your requirements.
Regards.