When you're booked in CW, how do you know if it's going to have 3 or 4 classes of service? Is the aircraft have a # after the 777-___?
I'm sure there's an easier way to find out, but I find out by doing a dummy booking on ba.com into First. If it's 3 class the system will book you into J and tell you that J is the highest class for that route.