Word of advice if you don't know already - as you are in CW I think you can use any free desk at the ITCI. When we were there recently there was only 1 BA desk open and with a queue. There were around 4-5 other airline desks manned but with no pax, however it was only when we saw people wandering over there to drop bags that we realised you could do that for CW (by which time we had got to the front of our queue).

Do use the showers in the Wing - really great although have not used the BA lounge before as I always to to the Wing. Also get a bite to eat there and allow around 15 mins to get to the BA gates.