Approval of an uploaded book - how long does it take?

I do alot of epubs. It wasn't until this morning that I decided to open an account in the ibooks store for selling free books. I actually did not do this with the intent of selling I just did it because I needed to know the procedure in which Apple uses when someone uploads a book. I would love to know ahead of time when I finish a book that it will be accepted and approved in the Ibooks store rather then giving the client the book only to find out later that even though the book passed various validation there is a proble with it when uploading to the ibook store.

In my case I just finished two books, one is a Read Aloud book using EzPub Creator and the other is a fixed layout childrens book. I need to know when I upload these two books to my account how long will it take for me to be notified if the books are approved or if there is a problem?

I have been using lulu.com as a third validator ( I use Sigil , then Epub Checker , then upload to Lulu. But Lulu has an option for the book uploaded to be just for me and not for sale and I can delete anytime. Only problem is they take forever for an approval or denial on the book. So what I'm asking is can I do a similar procedure with ITunes connect where I upload the book(s) and once they are approved I can remove with no problem?