Star Wars concept artist Ian McCaig recently spoke at the Art and Industry of Imagination conference. He spilled some beans on the Han Solo film:
Lawrence Kasdan actually wrote the script for Han Solo before he began work on VII, and that it is (paraphrasing) ‘By far the best Star Wars script, and one of the best scripts period, that I have ever read. I laughed, I cried, I did all the things you should do when reading a good script. You’re in for a treat.’