I think CRT use volunteers for tunnel bookings. Overall it's important to encourage fat boat owners to book their tunnel transit. This makes it more difficult to charge a booking fee or limit transits to, say, one per day. It used to be Fridays only, I don't know what happened to that. Half a dozen on the same day seems a bit excessive. On the other hand, having nine narrow boats delayed is not great for the majority population. It seems we narrowboaters have to give way to everyone else these days.