It as to do with the distribution of trigrams when they are spread in a circle. There are two ways of doing it, so you will have to look in the middle of the book. This appears in other hexagrams. NOrth meaning time to think and South meaning time for action.
I don´t know if this is the case in this hexagram.
I´m away for a while so don´t have the books with me.
Cheers
TEO