Thanksto @ether_tsubuyaki for the heads up on this!
The scenario book for Zero no Kiseki has been confirmed for a July release. The book will cost 2600 yen, and will have 664 pages. This will be the fourth scenario book for the Kiseki series, following up the books for the original Sora no Kiseki trilogy.
I will have more information on this book as it comes out.