Earlier production dates don't necessarily result in earlier release dates. Studios tend to in part plan their release schedules based on the types of movies they have in the wings and some types of movies are best released at certain times during the year, which is why we tend to see big action/escapist films in the summer and more serious fare in the fall. (There are even times where studios tend to release the movies that they have less confidence in - but let's not go there with regard to the Depp/DS film.) If Warners were to indeed decide that the Depp/DS film is the type of film that would do best with a fall release, it really wouldn't matter if it was to go into production in, say, July '09 or January '10 because in all probability it wouldn't be ready for release in fall '09 if it only began production in July, so both start times would most probably result in a fall '10 release. Also, studios tend to plan releases around which films the other studios have coming out as well as what other films a particular star has coming out. For example, if another studio announces that their film with Depp will be coming out on Friday, November 26, 2010, Warners would want to release the DS film at least a few weeks before that date or a few weeks after so that two Depp films aren't in direct competition with one another. (Actually, Friday, October 30, 2010 might be an ideal release date to capitalize on Halloween. Are you paying attention, Warners?
Though, of course, that would completely depend on whether or the not the film can be completed by that date, which at this point is still a bit uncertain because everything is still up in the air so much.
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