I had a problem with bank transfer for an online booking on www.klm.dk
I called the internet service desk for this issue and then I asked about "how to book an E class when N is available without paying the 30-40 EUR telephone booking surcharge?"

The answer: call us, the internet help desk, and we will book it manually for you with only the online service fee to be added. But don't try to call the reservation office she had to repeat it twice as I thought I didn't understand correctly... and I booked a ticket the same day this way.

sometimes they do answer "this IS possible"