I have a scene setup in Homekit using my thermostats where, when I trigger it, it immediately sets the correct temperature, but then immediately drops the upstairs temp by 1 degree (see gif). Both thermostats are setup the same way. This works fine if I use heat or cold, but not if I use auto. This is a tiny thing, but it’s driving me crazy because I can’t figure it out! I thought my thermostat app settings were conflicting, but I confirmed that they match.
Any ideas? https://gph.is/g/aK8yP7e
This might be due to a setting, and I can’t remember the exact terminology, something like “swing “ or “differential”.
It’s essentially to keep the system from oscillating between heating and cooling.
Can’t find it in my ecobee settings at the moment, but something to look for.
Which thermostats are you using? I have two ecobee units and when programming through their app everything works fine. When I try to use Homekit on the latest os release everything goes super wonky for me.
I too am using Ecobee and I’m aware of this setting and it’s turned off 
Shouldn’t be an on-off setting, I don’t think. It’s the reason one of your thermostat says 70-77 and the other is 61-82. That’s 7 degrees and 21 degrees.
I could be wrong, but that’s my line of thought.
Edit: maybe just setting Desired heat and Desired cool would allow it to work. If the difference is 21 degrees, it might not be possible to set Heat to 71, making cool 92, which is perhaps out off range.