No, there isn't a lounge provided for BA customers, the route is probably being tested out for viability at this stage. There is a lounge for Priority Pass customers, I'll put this in the Lounges thread in due course. This is the only lounge in Terminal 2 CGN (and there isn't any provision in Terminal 1). It's comfortable but the food and drink provision is at the basic end of the Europe's shorthaul lounges. It's on the level above the main airside concourse, immediately to the left of security and clearly signposted.