The phrase "embargo date" refers to a specific date when certain information, news, or products are not allowed to be released or accessed until that date. Full definition
Marvel Studios reveals the social media and review embargo date for Anthony and Joe Russo's 2018 film, Avengers: Infinity War. (screenrant.com)
Early embargo dates are usually a sign of a publisher's faith that their new releases will gain glowing reviews, which is something that rings true here. (gamesasylum.com)
It remains unknown if there is a specific embargo date or if the new products will be officially announced today. (goodereader.com)