Cat B will be a week to ten days depandant on your driving ability. You will then be trained on Landrovers so you will do about another 5 days of that. Enjoy DST, read this thread to get an idea about how w*nk and bullsh1ty it is there.
I was told they allow 11 days on the road for C and a further 5 days for C+E. Can't remember how long the theory took but I was there for 7 weeks all together (one day hazard awareness and 5 days fams).