I installed my own thermostat today. A Honeywell smart controller, with four time settings per day and some brains to dynamically adjust the temperature to the target on time.
The theory is, it learns how to most efficiently run the system, by tracking how long it takes to heat up/cool down. So that it knows that if you want it to be 68F when you wake up at 6am, it’ll start the cool/heat cycle before 6 to bring the temperature up/down to the target, and then keep it there.
Theoretically, this will save some $$. We’ll see.