I have published 35 books, about 108 if you count editions. I learned long ago that I should wait until I approve the proof of the book sent to me by the book manufacturer before I start to take orders.
Today I received the proof of The Unelected President novel and sent back my approval to print it with no changes. Last I heard, they expect it will come off the press on September 16th. Only when you approve the proof can you be confident about ship dates.