If you can catch a few of the livebait size carp which might be hard work you need to fish them on a dumbell rig with bait about 12" under the surface. Ive had a few out of rushes this way and i do know some 50+ have also been caught on the rig while i have been there. By using lives you are at least targeting the cats and not also the carp which will take a lot of so called cat baits such as meat, squid, worms, pellets etc. You will catch them on the boilie and pellet but the takes on lives are something else. Just make sure you are using proper gear for them, i advise catfish pro hooks and 40lb big game leader line for hooklinks on the lives, this is seriously abrasion resistant and keeps tangles to a minimum. Braids are a no no on the lives due to tangles.
PS. Steve when are you going as i'm also on during August