Star Wars Celebration is an event that has been held 10 times since it was first introduced in 1999 (to coincide with the release of The Phantom Menace). As its title suggests, the convention is a gathering for fans of a galaxy far, far away, bringing moviegoers together as they attend panels and meet stars from the films. It's similar to San Diego Comic-Con, only the focus is exclusively on Star Wars.
With the franchise back at the forefront of pop culture thanks to the new era of Disney films, Celebration is an event that takes on an even greater importance now. Instead of simply reflecting on the past, there's always new content to promote. Last year, fans learned some intriguing details about the characters in Star Wars: The Force Awakens and were treated to the second teaser trailer for Episode VII (the one that featured Han Solo's famous "Chewie, we're home" line). Given that the Mouse House is releasing a new movie annually for the foreseeable future, 2016's Star Wars Celebration in London would be a great time to push Rogue One: A Star Wars Story, the first spinoff film. Indeed, something has been planned for the anthology movie.
In a press release, Lucasfilm announced that Rogue One director Gareth Edwards and Lucasfilm president Kathleen Kennedy will host a panel on Celebration's opening day, July 15, 2016. They will be joined by currently unnamed special guests, though it's likely these are members of the cast. Rogue One mainly features a bunch of fresh faces that fans are unfamiliar with, so Celebration is the ideal outlet for the actors to discuss their characters and what they're all about - under the watchful eye of the studio, of course.
It also wouldn't be surprising if Edwards brought some new footage with him to Celebration, perhaps a second teaser for the film. Ideally, the panel will provide confirmation concerning an oft-rumored Darth Vader appearance. It's long been reported that the classic villain has a role in Rogue One, though nothing has officially been said yet. Vader being in the movie makes a great deal of sense, since he would likely be leading the Imperial forces trying to stop Jyn Erso and her crew. As for why his (potential) involvement has been kept under wraps thus far, it's the same reason why Lucasfilm held off on using original trilogy characters in Force Awakens marketing for a while. They want the attention to be on the new additions right now so they don't get overshadowed by the legacy characters.
Celebration 2016 runs from July 15 - 17, 2016, which is a week before San Diego Comic-Con. This has caused some to wonder if Lucasfilm will have a presence at the latter, opting instead to use only their convention to usher in the next wave of Rogue One marketing. That could very well be the case, especially since it's been rumored that Disney plans to bypass Hall H presentations this year. However, the studio would be wise to put something together for the American-based Comic-Con. Though anticipation remains high for Rogue One, it's a different animal than The Force Awakens. Some of the uninitiated may be unsure of where it falls into the timeline or why they should care about a story so disassociated from the main saga. Panels at back-to-back major events could be extremely beneficial. One way or another, July is when fans should start learning more about Rogue One.
Rogue One: A Star Wars Story opens in theaters on December 16, 2016, followed by Star Wars: Episode VIII on December 15, 2017, the Han Solo Star Wars Anthology film on May 25, 2018, Star Wars: Episode IX in 2019, and the third Star Wars Anthology film in 2020.