Whenever I've seen theaters do this type of thing, they do it before the published show time. Related content first, then at the published show time trailers st

Whenever I've seen theaters do this type of thing, they do it before the published show time. Related content first, then at the published show time trailers start, then a bit later the actual movie starts. If you don't want spoilers, then you just don't go in until the published show time.