Hi Alex, I have a sensor light blueprint that I think you will like. In my FAQ it shows you how to fix this problem.
Blueprint: 
Sensor Light - Motion Sensor - Door Sensor - Sun Elevation - LUX Value - Scenes - Time
The FAQ in the post: click here. It is under the heading;
REF - ALS-2
LUX / Illuminance Sensor With A Default Value
You would just make the sensor your motion sensor that “unknown or unavailable”.
Blacky 