Ecobee4 with HomeKit Controller - always defaulting to Auto Mode

I recently switched to the HomeKit Controller to locally manage my Ecobee4 thermostat. Everything works great, except it keeps defaulting to Auto-Mode (high temp and low temp range) instead of just Heat or just Cool as I want it, and keep setting it too. But after a little bit of time it’ll jump back to Auto mode.

Any idea why it might be doing this?

I see in the logs that climate.turn_on is what’s changing it, but I don’t know why. I don’t use Hass to turn on/off the HVAC system, I only use hass to switch Comfort Settings from HOME to AWAY. So I have no clue why it would be sending turn_on commands. It also sends them at complete random times — not times when hass switched comfort modes.

I have set it to Heat in its HA device entity, I’ve set it to heat on the ecobee itself as well.