Harkonnen had a long-term project to make dynamic shadows that would change throughout the day, which would result in the solar panels being fully lit for at least a moment at noonish, but I got the impression that side-project was eventually canned due to, uhm, personnel issues.

Aren't shadows baked into the texture? Adding another dimension to the texture matrix of all structures seems dubious.

Did something dramatic happen?

Yes, Paul of house Atreides happened