Since no one has responded I guess I will.
I don't know if the U20 needs an epoxy barrier coat because to my understanding you only need one if the resin used below the waterline is polyester. Since the boat was built fairly recent I would say it has a good chance of being vinylester and the epoxy coat is not needed. On the other hand the boat is intended to be dry sailed so maybe the designers decided polyester would be adequate.
In my opinion the money spent applying the barrier coat, then applying bottom paint, then cleaning the bottom regularly, then re-applying bottom paint would be better spent on a lift. It doesn't take much of a lift to get the U20 out of the water. Maybe a couple 1000# pile-mounted hand-crank davits, or maybe a floating lift that plugs into shore power - dunno but I'm interested in an economical lift system myself.