There are some really crazy theories in this thread. There is absolutely no way SE changed the release date for FOMO or to fight Blizzard.

It is most definitely an issue that came up internally with the state of the game or servers. It's not something they would do unless it was absolutely necessary for the stability of the game.

It is a huge deal. Were talking millions of dollars to recertify the game with companies like Sony on the PlayStation store. It is not something they would do just to stick it to Blizzard or some other competitor.