It could be possible – and hear me out because this may seem like crazy town at first – that they are just revealing book on their own timetable (or Disney's) rather than the entirely arbitrary convention schedule.
I mean, Gen Con reveals are neat and all, but it's not like it's necessary to make a big splash to have a good game.
Ok. One last time.
Every year at GenCon they do a 90 minute panel going over their entire business. The CONTINUALLY use this as a time to announce upcoming products. In fact they did exactly that with Imperial Assault and X-Wing this year (I only really pay attention to their Star Wars stuff). There is nothing wrong with people anticipating this to happen for the RPG line.
However, it appears they have already announced everything they are working on that they want the public to know. Two books for FaD, a book for AoR and a book for EotE is a pretty good amount of upcoming products. Additionally, if they ARE doing Force Awakens stuff, they likely cannot announce it until September.