I can use homeassistant to change either brightness or color_temp, but if I try to change them at the same time, the bulb brightness seems to go about half-way and then fade back to it’s original color. I have tried different variables for birghtness and temprature, (such as _pct), they all seem to have the same effect.
Maybe the brightness gets applied first and when the temprature get’s applied, it sends a new command with the old brightness, thus turning the brightness back to it’s original color.
More details: https://github.com/home-assistant/home-assistant/issues/14568