I have e-mailed DVLA and asked them if any exemption exists - I will copy and paste that reply when I get it
Here is the reply from DVLA....
Thank you for your email received on 29/2/12. Your email reference number is 862502.
There are certain recovery vehicles which are exempt from the normal driver licensing requirements, which apply to larger vehicles Regulation 51(1) (p) of The Motor Vehicles (Driving Licences) Regulations 1999 as amended. Regulation 7(4) of the above regulation as amended allows the holder of a full Great Britain, Northern Ireland, or EC/EEA category B entitlement to drive an exempted goods vehicle such as a recovery vehicle which is:
A vehicle fitted with apparatus designed for raising a disabled vehicle partly from the ground and for drawing a disabled vehicle when so raised (whether by partial superimposition or otherwise) being a vehicle which -
(i) is used solely for dealing with disabled vehicles;
(ii) is not used for the conveyance of any goods or load other than a disabled vehicle when so raised and water, fuel, accumulators and articles required for the operation of, or in connection with, such apparatus or otherwise for dealing with disabled vehicles; and
(iii) has an unladen weight not exceeding 3.05 tonnes;
A recovery vehicle may also fall within the exemption 51 (1) (q) which is :-
a passenger carrying vehicle recovery vehicle
Regulation 7(7) of The Motor Vehicles (Driving Licences) Regulations 1999 as amended allows the holder of full Great Britain, Northern Ireland or EC/EEA category B entitlement to drive a vehicle in category B+E where:-
(a) the trailer consists of a vehicle which is damaged or defective and is likely to represent a road safety hazard to other road users,
(b) the vehicle is driven only do far as is reasonably necessary in the circumstances to remove the hazard or obstruction, and
(c) he receives no consideration for driving the vehicle.
NB If the driver holds only automatic entitlement for category B then he may only drive vehicles in category B+E with automatic transmission.
Recovery vehicles which do not meet the above exemptions will be subject to normal driver licensing requirements and will require the licence holder to have the appropriate licence category.
Do not reply to this email. If you wish to contact us again about this response then please use our Reply Form or copy and paste the following URL in to your browser:https://emaildvla.direct.gov.uk/emaildvla/cegemail...
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Customer Enquiries Group