Not used as much, but turning on the A/C before arriving home from a long trip sure is nice. That obviously requires the internet, but I refuse to use a third party.
Downsides - 2 dead smart switches in 2 weeks. They aren't cheap and should last a lot longer.
The same goes for hvac. Configuration might be more complicated but I'd rather walk into a sweltering home than have a massive power bill when some script kid pwns my system and sets the temp to 50f for two weeks.
Humor aside, I'm still interested in what you are referring to. I'm not aware of a way to do that, but maybe didn't know what to look for.
I was interested in a thermostat with an API that worked locally, no internet needed and no 3rd party required and that is what I went with. Paired with the alarm system (old school, hard wired, it doesn't know what the internet is) it can alert me when the A/C is on, but a window is open.
A 7 day may not be sufficient for an 8 day trip unless you can have a friend or family member drop by to adjust the settings, but I'm definitely going to keep this in the back of my head for when I inevitably need to upgrade my HVAC.