HAVC: Automatic, Heat, Off - what is it and where do the values come from?

I’m having Homematic-IP thermostats in every room connected to a Raspberrymatic as a dumb bridge for Home Assistant. Since I’ve had a quite complicated node red automation that I’m about to recreate, I found out that those thermostats support three different modes via Home Assistant: Heat, Automatic, Off.
Whenever I hit one of those mode, the preset temperature changes. But the question is: Where does it come from? For example, off leads to 4,5°C, some automatic settings lead to 21°C other to 22°C. Heat gives different values to.

But how do I set those values? I didn’t set those numbers in Raspberrymatic so its quite confusing.