Ok fine .. so a white background against light blue or gray sky's, then copy from edge to edge all 4 sides, only dark panel is small copy on bottom. so kinda a fail for a billboard advertisement.
How to correct next time same ad.
The general layout is good, but a main dark panel against sky with white letters is contrast,
the copy next to main another color panel you can harmonize is good way,
then bottom panel white with black copy would read easy at break neck speeds.
One thing this billboard size is lacking greatly is air space around the copy & simple contrast
What do have is 3 good simple messages, contrast makes the difference during the day, you must see the sign area 1st then the main copy, 2nd copy, then 3rd at bottom.