Hello,
I have the same issue.
Really annoying that widgets in Homey do not show temperature from both sensors in AF mode and I cannot trust the floor top limits.
Actually there is a setting for the maximum floor temperature and I use 26. I just need to know that this mode works and my floor in living room will not be warmer than 26 degrees. Last test of AF mode was strange. It was 3 degrees colder inside the room than the setpoint. Homey app showed that it is heating. I checked the floor sensor by switching to F and found that the floor sensor showed less degrees than the internal sensor. How that could be?! Cannot trust AF mode and use F for now but this is inefficient.
Did you find the solution?
I am thinking of using F mode since it is stable and connect my heatit devices with a dedicated temperature sensor and weather forecast to change setpoints dynamically using Homey flows.