Correct me if I'm wrong but I think foreign countries to the US have been getting blockbusters earlier. I don't know how often and sometimes we're talking days but still. That used to be the other way around.
It would be wise to release the teaser online at some point lol
Even though it's Nolan marketing still has to kick into high gear to get people to see it in theatres.
Holding back on the teaser is just increasing demand and intrigue. It’s not impossible to get a copy if you really want it. The marketing of the movie I’m sure will mirror some of the themes from the story. They just can’t spoil much yet.