I would be very surprised if there's anything in there approaching that size, unless of course some larger fish have been stocked since last year. We dropped out of the syndicate as we felt that the average size of the fish on offer was low. Since more people have been fishing it over the last couple of years a lot more bait will have gone in so you would expect the fish to put on weight, but I still think you'd be lucky to see anything over 20lb. It's a nice place to fish though and the owners are lovely people.
I would avoid maggots, it's rammed with Gudgeon, they tend to get used as bait for the Cats. Stick to decent boilies and you should pick up Carp, however, don't expect any monsters, the average size is quite low.