First Basic(A) rebooking
 

My flight back JFK-ZRH-DUS had no availability in A for the earlier flight LX17 because of the married segments, while JFK-ZRH had A availability.
When arriving at the airport early on the day of departure, do you think I can get the earlier flight (if A is available then) without the rebooking fee (€410)?

Since it’s DACH & not cheap A anyway, maybe, on UK tickets no way, do let us know ?

I'd be curious to know how this plays out as well.

By the way, it's not just a question of being "available", but also "available" for an existing booking as opposed to a new booking. Unfortunately, two different things in the greedy world of LHG. In addition, I doubt they will give you a pass on the rebooking fee and I can see a fare up charge too.

Final thought, the food at the wining and dining section of the lounge is BAD so it won't be an entertaining long wait if you get there early and decide it's not worth the $ or is not available.