It was recently announced at C2E2 that a three-issue comic series by Phil Noto that would tie into Rogue One: A Star Wars Story would be released later this year. Now it appears that Marvel have cancelled the series, with retailers hoping to stock the series having been told that their orders will now not be filled.
According to Bleeding Cool, the main reason behind the cancellation is rewrites. With the challenge of writing and illustrating a comic that links directly to a movie that isn't out yet, which has itself undergone reshoots and editing, ensuring a solid story that connects seamlessly has proven to be too much for the comic book creative team within the time and budgetary constraints they were given.
Perhaps after Rogue One's release the team will revisit the series to fill in the extra details fans were promised, but until then the comic is no longer available to pre-order.