Just a quick question, can a new driver drive now without his cpc or does he have to do it at the time of his test
A new driver can drive straight away if a) they are not driving professionally or b) if they hold acquired rights - eg passing a car test before 1997 so holding C1.
Apart from that, to drive professionally, a new driver has to complete Mod 2 (case studies theory test) and Mod 4 (practical demonstration test) which can be done as soon as they hold the appropriate provisional licence or at any time after that.
Having done that, there is a derogation allowing them to drive professionally without holding the card physically until they receive it. (I think there’s a time limit - 15 days?? - but I cant recall that at the moment).
Hope that helps, Pete 
Thanks Peter much appreciated.
don’t you need to keep your certificates on you until the card arrives in the post? 
What certificates?
It would be a good plan to carry the Mod 4 pass certificate but I’m not sure it’s actually a legal requirement. But could save a long discussion at the roadside.
Pete