dont know of this quote found on posterwire helps:
"The order of actors names may be set in stone via contractuals, but the design/layout (at least in some regard) of the movie poster is not. This is the recipe for the not-so-uncommon phenomenon of actor credits not lining up with their image on a one-sheet... Youll also see the credit order versus actor groupings battle in movie posters for ensemble dramas. There are many other variations and solutions to this type of credit billing problem for example, a stars name could appear in the middle and above the costars credits and be considered top billing. (Although it doesnt always solve the problem).
Since film advertising art directors are already limited in what they can do with regards to actor placements (both in name and likeness) in one-sheet layouts, its understandable that most film account executives overlook this minor credit lineup glitch. This is just one of the many hoops that film key art has to jump through (like the films themselves) before it reaches your local theater lobby."