Upgrade advertised at the check in counter for MAN-IST.
When I inquired about the price the lady told me she has no idea as normally no one ask and called the supervisor who produced 173GBP as offer. As the check in counter was completely empty (I was the only one) all the other ladies were listening and they recommend me not to take it as the lounge was already closed (It was the redeye flight departing at 23.40) and the flight was quite empty so the chances to get some sleep were big (which turn out the be not true due to two hiper-energetic childs
)