Ol’ George paid a visit to the Rogue One set:

Gareth Edwards said:

There are two things that are incredibly surreal that you could do in your life, and I think number two is having to show George Lucas your Star Wars movie. Like it was really crazy, and I think number one is to be George Lucas and have someone show you a Star Wars movie. And so I felt for him and he was incredibly gracious. He joked a lot about how we should do more in the computer and not build so much. We didn’t take his advice, we tried to shoot as much in camera as we could.