The biggest problem for any movie moved from December to early summer is that the schedule of promotions must be dialed back. Principal photography is starting to wrap up. As the post-production phase is started, re-shoots and loop recordings are made and it is easy to schedule actors for interviews and talk shows. The Hollywood hype machine can move in lockstep with post-production and a series of teasers, trailers, and TV ads.

With the six month push back, you risk over-exposure and ennui from the casual fans and increase the change some crucial story elements may be leaked. This won't effect the quality of the movie, but it will effect the box office and the immediate perceptions.

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Keeper of the Jabberwock