Technically speaking, this is a rumor at the moment, as Disney/Lucasfilm STILL can’t talk about Rogue One until the new Mission Impossible movie hits theaters, but in all likelihood this is legitimate. The BBC spotted the information on Jonathan Aris’ Spotlight Page. The site is essentially an online CV for actors/agents people to use and connect, so it’s a pretty official thing, people wouldn’t want to lie on. Plus the site was pretty spot on with casting news just prior to The Force Awakens starting up production. So there’s precedent for this being the real thing.
The information shows that Jonathan Aris is playing Senator Jebel in Rogue One. Now, obviously that’s not a lot of information, and even the name may not be the same in the movie, but it does tell us that he’s in the film and will be playing a Senator. In Star Wars: A New Hope, one of the things Moff Tarkin mentions in the film is that the Emperor had finally disbanded the Senate around the events of that film.
So in the time period of Rogue One, that means the Senate would still technically be around, and thus would make sense for a Senator (perhaps one sympathetic to the Rebellion) to be in the movie. Obviously we’re just speculating, but with filming set to start next week, hopefully we’ll learn more soon!
Star Wars Anthology: Rogue One hits theaters on December 16, 2016.