First off dude, Kiefer has a made a good deal of alterations to the CBL protocol since the books' release, and should be coming out with a 2.0 version soon. Timing of the backload can vary based on:
-Time you train (during the week, time of day, etc)
-Amount of Carbs you take in during backloads
-Goals (strength, gaining muscle, cutting)
You REALLY have to experiment with this protocol. You're really going to have to play around with it. MOST on on CBL forums backload the night BEFORE a morning workout, and the night OF a afternoon/evening workout. Decent rule of thumb. But it depends. Some people backload every night, some 3x a week. You have to see what works for you.