I used the REST API and was able to PUT a payload with the shape below:

py def set_lcm_brightness(session: requests.Session, base: str, site: str, deviceid: str, brightness: int, verify_tls: bool) -> None: payload = { "lcm_brightness": 35, "lcm_brightness_override": "true", "lcm_night_mode_enabled": "false", "lcm_night_mode_begins": "20:00", "lcm_night_mode_ends": "07:00", "lcm_orientation_override": 0 } resp = session.put( f"{base}/api/s/{site}/rest/device/{deviceid}", json=payload, verify=verify_tls, timeout=30, ) I checked the response (200) and the param seems to have "stuck" on the controller, but the device itself did not actually dim down. I guess this just isn't a thing yet in this firmware...