This is just something I noticed. Kakashi is not wearing his headband in Chapter 604 on the last page.
But in the links below Kakashi always had his headband on.
http://www.narutobase.net/manga/Naruto/599/11 (young kakashi)
http://www.narutobase.net/manga/Naruto/602/18 (young kakashi)
Is this Kakashi a zetsu clone on the last page of Chapter 604?