i don't know when you had this but it doesn't seem to be covered now as their terms state-
"Breakdown assistance is only available for cars, vans, minibuses or motorcycles"
"Assistance will also be provided for a caravan or trailer which was on tow at the time of the breakdown"
perhaps the rules have changed recently with AA?
i am just going to join the caravan club for a month and get green flag i think. you don't need to stay a member to get the cover, only to get started you need a membership number.