Apple (AAPL) on Tuesday sent out invitations for a press conference scheduled to take place on September 12th at 1:00 p.m. EDT, 10:00 a.m. PDT. The invitation doesn’t reveal the nature of the event, but it doesn’t have to — it’s all about Apple’s next iPhone, which is expected to be in line with the flood of recent leaks: It will be a little taller, a little thinner, and a little stronger than Apple’s current iPhone. Apple’s new iPhone is expected to go on sale on September 21st, and preorder availability could begin as soon as September 12th, the same day the phone is announced. Be sure to check back on September 12th for all the news as it breaks.