When putting the car in park, the touch screen should offer an option to hold the current HVAC settings when the car is exited and locked. This would be useful when some living being — such as a pet or child — is left in the car, or when you know that you will return soon to continue your trip.
Of course there should be some reasonable time-out, e.g., after 60 minutes (earlier if the battery runs low), HVAC should shut down. IMO there is no need to make this configurable. Just offer a single button “Hold HVAC”.
Currently a similar function can be done from the phone app, but when HVAC is turned on from the phone, it will shut down once the target temperature is reached. The phone app feature does not serve to “hold” the current temperature. Besides, it is clumsy to use when you could as well just press a button on the 17″ touch screen.
Feature was added around software version 2017.42 (Camper Mode).