The Bond books are a crucial foundation and should be gone through with a timetable, perhaps one book a week. Do the easy ones first and aim to have the 13+ books done a month before the exam. That gives you plenty of time for the GL VR and NVR papers. Do not even look at the papers until then - doing so will only frighten you and your DC - the difficulty is that of the 13+ Bond books. Also, if you run out of Bond books there are others in the shop you might want to try, particularly the intro to VR and NVR books as they coach in a different manner to the Bond books (these can be done before the Bond books as they are easy but provide guidance which the Bond books do not).
Eek-we're Essex, but not Redbridge. Are the exams different in Redbridge and is it common to do the 13+ Bond books beforehand? We're only on the 10-11 ones!!