How about calling them? Moreover, I don't see the point in booking business on LG. The seats are the same. Apart from different food and lounge access (given that LUX does not have a fast track), you don't get much for your money (or in this case your miles).

Especially given that they currently have great deals in Y on pretty much all their destinations. ARN for 99€ with checked bags can't even be beaten by regular LCC prices.