Steve,
Just for clarification this story was carried last week in the main transport trade newspaper - Motor Transport. According to their figures (I guess supplied by Superfast) the two boats carried just over 40,000 freight units in 04-05 year this incidentally was up from 32,000 the previous year (over 20% increase!!).
The Over 20,000 figure is a division of two (two down to one boat) However in my experience it very hard to schedule drivers and vehicles when a service operates that infrequently. Therefore for some they will say (stuff it) and I would put a decent bet on there figures being under 20K next year
Companies to my knowledge using the Service AAR Craib (Aberdeen) Curries(Dumfries) G&S (Glasgow)
Regards Monkeys Husband