Director Gareth Edwards' Rogue One: A Star Wars Story opens in theaters near the end of 2016 and will serve as the first in a planned series of standalone Star Wars movies - that is, films that take place in a galaxy far, far away, but are not direct continuations of the central saga narrative that was picked back up thirty-two years after Episode VI: Return of the Jedi by Episode VII - The Force Awakens (and will continue in 2017 with Episode VIII). Set to follow Rogue One in 2018 is a currently untitled young Han Solo movie that Phil Lord and Chris Miller (21 & 22 Jump Street) are directing based on a script by Episode VII co-writer Lawrence Kasdan and his son, Jon Kasdan.
Walt Disney Pictures and Lucasfilm have reportedly auditioned (quite literally) thousands of actors to play young Han Solo, with the alleged candidates having varied from being established rising talents in Hollywood to industry newcomers thus far. The shortlist of actors under consideration to take over the iconic Harrison Ford role has now apparently been shortened to a far more manageable total of a dozen or so actors, which may come as a surprise seeing as production on the young Han Solo adventure isn't slated to get underway for another year, in early 2017 (from the time of writing this).
Variety reports the the reason the young Han Solo casting process is moving along so fast is because Disney/Lucasfilm may, in fact, have plans for the new Han Solo actor to make a cameo in Rogue One. Although Variety's report indicates this news should be treated as a rumor for the time being, it is not outside the realm of possibility; after all, Rogue One will tell the story of the Rebel mission to steal the original Death Star's plans, and there ought to be some overlap in timeline between that storyline and Lord/Miller's film (which will take place within a decade before the events of Star Wars: Episode IV - A New Hope).
The idea of young Han Solo appearing in Rogue One (as noted in Variety's report) brings to mind how Marvel Studios is introducing Tom Holland's version of Peter Parker into the Marvel Cinematic Universe by having him show up in Captain America: Civil War, before his own Spider-Man solo movie. However, whereas Spider-Man was part of the Civil War source material and his inclusion there makes sense for related reasons (though his role shall be a bit different), it is arguably not as clear right off the bat how Han Sol would be an organic addition to Rogue One's narrative - given that the Star Wars movies have never indicated that he had any connection to the rebellion against the Galactic Empire, prior to his and Chewbacca's fateful encounter with Luke Skywalker and Obi-Wan Kenobi. (The old Star Wars Expanded Universe, aka Star Wars Legends, on the other hand...)
Regardless of whether the Rogue One story pans out or not, Variety's article indicates that the young Han Solo role will be officially filled sooner than later. The shortlist of candidates mentioned in the site's report includes previously-reported contenders in Miles Teller (Whiplash), Ansel Elgort (The Fault in Our Stars), Dave Franco (Neighbors), Jack Reynor (Transformers: Age of Extinction), Logan Lerman (Fury), Scott Eastwood (The Longest Ride), Emory Cohen (Brooklyn), and Blake Jenner (Glee). Seeing as there are other names on the young Han Solo actor shortlist too, it could wind up being someone else than those named here who actually lands the role.
Many Star Wars fans are still adjusting to the reality that someone other than Harrison Ford is going to play Han Solo in a movie, but others have already accepted so much and begun to narrow down the list of qualities that their ideal candidate should have. Some might find Teller a promising choice given his knack for playing fast-talking wise acre types with a vulnerable side, while others may prefer a Lerman type - someone likely to play Han Solo as innocent and good-natured, before he evolves into more of a cynical soul over the course of Lord/Miller's film. Lord and Miller have continuously defied expectations while taking on projects that many deemed a lost cause from the get-go (see 21 Jump Street and The LEGO Movie), so if there's anyone who can be trusted to make the right call on casting young Han Solo, it's them... even though it might not immediately seem like the right call, at first glance.
Similarly, Lucasfilm and its Star Wars story group has been effective thus far when it comes to creating connections between Star Wars storytelling than spans a variety of mediums, be they books, movies, or TV shows (see the appearances of original trilogy players on Star Wars Rebels). That is to say that if young Han does, in fact, have a cameo in Rogue One, there's fair reason to believe that it will be for an important storytelling purpose - and not just for the sake of some 'fan-service'.
Star Wars: Episode VII – The Force Awakens is now playing in theaters. Rogue One: A Star Wars Story will arrive in theaters on December 16th, 2016, followed by Star Wars: Episode VIII on May 26th, 2017, and the Han Solo Star Wars Anthology film on May 25th, 2018. Star Wars: Episode IX is expected to reach theaters in 2019, followed by the third Star Wars Anthology film in 2020.