The AA’s Ts &Cs read:
Unsafe, unroadworthy, unlawful vehicles,
that is
where in the AA’s reasonable opinion, immediately before the relevant breakdown or accident, Your Vehicle was dangerous, overladen, unroadworthy or otherwise unlawful to use on a public road. Without restricting the generality of the AA’s rights under this provision and Your responsibility to comply with all applicable legal requirements, please note that for a UK registered vehicle to be used or kept on a public road, and subject to any relevant exemption that may apply, the vehicle must have a current excise licence (that is, up to date vehicle tax) a current MOT test certificate and have in force valid motor insurance to the minimum level required under UK law;
Also, under ‘exclusions’ it says:
Trade transportation, that is
the recovery of any vehicles bearing trade plates or which the AA has reason to believe has just been imported or purchased at auction.