This was mentioned on another thread - but I thought I would start a new one....
For details of what the AA covers have a look here
In addition, assistance will be provided for caravans or trailers on tow at the time of the breakdown, provided that they fall within the above limits for UK Relay service only. A caravan or trailer of a length of greater than 18ft (5.5m) but not exceeding 26ft (8m) will be recovered provided that this can be done safely under tow.
Five Star 72 Hour European Breakdown Assistance does not cover any trailers transporting either motor vehicles or any waterborne craft.
So in the UK a trailer upto 8m will be recovered if it can be towed. This is OK if its the car that breaks down - but if there is a problem with the trailer then your stuck!
I take it this is when the "trailer cover" from Sea Start kicks in