Anime series are not known for divulging tons of trailers or artwork or anything of that sort so far in advance. You would assume that they would take a different spin on handling Sailor Moon, but being secretive really is the norm. This might be a bad example given the franchise, but the Rebuild of Evangelion movies have some of the most cryptic marketing out there before the movies are out, then once they're out, trailers and commercials and promo stills and everything abound.
Also, some merchandise is starting to creep out. A calendar/planner isn't much but it's something.