Ron Howard is a lock to reshoot at least 51% of the movie.
There is no way Disney is going to release HAN SOLO: THE STORY YOU ALREADY KNOW directed by Alan Smithee.
Provided none of the cast has other commitments past what was supposed to be the end of shooting just three(?) weeks away before this happened. A major reshoot is going to screw up the release date either way.
The DGA retired Mr. Smithee many years ago. Not sure what the alias is these days.