dcpc is for drivers working for hire and reward, to the best of my knowledge trade plates are exempt as they can only be used to deliver a vehicle on and you are not allowed to undertake any other work with trade plates on
(c)which is undergoing road tests for technical development, repair or maintenance purposes, or that is a new or rebuilt vehicle which has not yet been put into service;
My understanding is that being on trade plates with a vehicle that is in service but is just getting repainted would not be exempt BUT … I would call the DSA DCPC hotline on 0191 201 8112 to get a definitive
Wheel Nut:
Your mate is not driving “professionally”, he is simply delivering new or refurbished vehicles to his own customer.
A trade licence does not allow goods or passengers to be carried, it is simply a metal tax disc
thats my way of looking at it, you are not even suppose to park a vehicle on trade plates, my mate owns a garage and got done for parking a vehicle outside his home one night, left the trade plates in the window, nearly ended up loosing the plates for incorrect use, but just managed to get away with it as i was his first offence