Let me help clear up some of the confusion.
Many years ago Dr. Wile was asked to provide science materials for a homeschool co-op. He wrote what became the Exploring Creation with . . . series of books for middle school and high school. Jeannie Fulbright then wrote an elementary science curriculum which Apologia published. Apologia used to be Dr. Wile’s publishing company, then he sold it but still wrote for them. Eventually, he parted ways completely with Apologia.
Several years ago he started writing an elementary science curriculum, the Science in HIStory series of books. He did not want to be the publisher this time, so Berean Builders publishes his new books.
Berean Builders sells, but does not publish, the Apologia middle school and high school books. Apologia replaced the 2nd edition of General Science this past year. They did an okay job of it as you can read at Dr. Wile’s blog linked above in Sarah2106’s comment. I encourage you to read it as Dr. Wile gives a fair review of it. Because Berean Builders is a seller of the Apologia books only, they cannot continue to sell the 2nd edition of General Science when their stock of them runs out. The same goes for any company selling Apologia’s books, once the 2nd edition of General Science is sold out, it will be no longer available, as Apologia is not printing anymore of the 2nd edition books.
Before Apologia released their revised General Science book, Dr. Wile had already started working on a 7th grade book continuing his Science in HIStory series. You can read about that book, Science in the Atomic Age, on Dr. Wile’s blog here: http://blog.drwile.com/coming-soon-science-in-the-atomic-age/
SCM will be reviewing Dr. Wile’s new book when it comes out and will make a decision as to what will be our recommendation for 7th grade science. Until then, we still recommend Exploring Creation with General Science, 2nd edition. As HollyS mentions above, there are plenty of used copies available if you can’t get a new copy.