Great question — answering as the UphillTech team:
This really depends on the film. The average film that doesn't get a hyped release will show its first screenings, generally between 10 am and 12 pm (noon), whenever the theater opens and schedules the screenings. The new blockbuster release, though, generally includes screenings at midnight on Thursday night (assuming the release date is set for Friday). The only restriction is that the film can't be shown before its specific release date (usually a Friday)... usually... that seems to be changing of late. In the industry's ever increasing need to extend their opening weekend box office numbers, screenings have started to spill over into Thursday evenings. For example, with Avengers: The...
Full answer by Catija: https://movies.stackexchange.com/a/33661 (CC BY-SA 3.0).
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