User blog comment:SayuriDarling/The Demigod Diaries Official Discussion Blog/@comment-5440962-20120825222410/@comment-4531192-20120825231150

It most likely just redirected you to the US version of the site.

The two books are different because one of them is the UK version (see the publisher - Puffin Books). The reason why it says 12 days is because the book is not out yet in the UK, as pointed out by many of our (frustrated) British users.

Just get the version that suits you best. They're practically the same apart from the cover and the dialects used.