Zemeckis would replace the previously attached Paul King (Paddington) who dropped out of the project. Harry Potter producer David Heyman was also producing the film but he is also no longer involved with the film. There’s no reason given as to why they left the project. So, I’ll just chalk it up to creative differences, since that’s always the reason given when someone leaves a project.
I’m a big fan of Zemeckis who has directed films such as Back To The Future, Who Framed Roger Rabbit, Forrest Gump, Cast Away, The Walk, and a lot of other films. He’s currently directing an adaptation of the book The Witches. The guy is a super