Other mistake: During the final battle of the theatrical cut, in the future sequences, in at least one shot, you can see in one of the reflective surfaces of the room where Logan is being "sent back" that Rogue is the one controlling him and not Kitty. This is a remnant of a deleted sequence where Rogue is brought in to absorb and use Kitty's power after she was injured. The scene was cut from the theatrical release and the film was re-edited so that Rogue wouldn't appear in the future and Kitty is the only one "sending" Logan, but at least one shot where she's visible in a reflective surface was left in as an "easter egg" for fans. Still, it is technically a mistake in the theatrical edition. (The Rogue version of the scenes were included subsequently in the extended "Rogue Cut" of the film, and in the special features, this intentional mistake in the theatrical edition was confirmed by producers).