The Saskatchewan Entertainment Expo recently revealed that Billy Dee Williams (Lando) will be cancelling his appearance due to filming conflict. It is also worth noting that his Fan Expo Canada show in Toronto has also been cancelled as shown here.
Screen Rant best sums it up -
On June 28, 2018, the Saskatchewan Entertainment Expo Facebook page announced Williams will not attend as originally intended "due to a film schedule conflict." For his part, the actor expressed regret and looks forward to going to the convention in 2019.
The fact that Williams' reasoning was specifically described as a "film schedule conflict" points to him being in Star Wars 9. He currently doesn't have any other feature-length productions on the docket, and the timing of all of this adds up. Abrams will commence principal photography later this month, while the Saskatchewan Expo takes place September 15 and 16. Of course, major studio tentpoles like Star Wars take several months to shoot, so it's reasonable to assume Williams would be preoccupied with reprising Lando for a while. For comparison's sake, production on Abrams' The Force Awakens ran from May to November 2014. Even if things move along at a quicker pace this time around, filming should take longer than two months.
It'll be interesting to see if Williams is included on the official Episode IX cast list when cameras start to roll. As evidenced by keeping Frank Oz in The Last Jedi a secret, Lucasfilm isn't beyond preserving the surprise of a legacy actor returning. That being said, if Lando is in Star Wars 9, it'll likely be for a more sizable part than a single-scene cameo - especially since he can't work a convention appearance around the shooting schedule. With Star Wars 9 in need of a veteran leader to help guide the young leads of the sequels, General Lando Calrissian could be called upon to save the day again. Maybe he'll even get to fly the Millennium Falcon one last time.
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