"err.. I'm afraid I must be stupid, I cannot figure what means:

B, G, H, K, L, M, N, V, W, Y, S, S2, S3"

They indicate the valid booking classes for mileage accrual. For Advantage members based in the US/Canada/Mexico and Australia these are valid for mileage earning on BA.

The 1st character of the Fare Basis will indicate the booking class. For a MONE5, the booking class is M which would be eligable for miles. For members based elsewhere, the MONE5 will not be valid for mileage accrual on BA flights.

Dave