Just had a look at their website and there is no mention of it, however noticed they are now charging over £6 per metre + power a night !!
Much as we like it there that's starting to get a very pricey, the improvements will have to be spectacular.
I just got a reply from St Kats regarding visitor's berthing:-
"Unfortunately we will not be taking any bookings from next month as we have major refurbishment works taking place in the marina, estimated to last approx. 9 – 10 months, however we may be able to accommodate bookings in August only – depending how well the works go and if there is availability we will try our hardest to accommodate you."