It depends a bit, Gilles, on what type of 'holiday specials' they are — i.e. what sort of business XXX is in; it might, for exalmple, be just flights (to go on holiday), or it might be accomodation (séjours, ...), or it might be specials in an unrelated industry, but at holiday times or for holidaymakers.

But it seems from your context as if this may be only indirectly relevant, so maybe it doesn't matter anyway!