My Wife reserved a seat on the same flight as the one i was booked on to return to the uk, a few months before i came out. At the time my wife was still waiting for her interview (which we didn't need in the end) so for about 10 pounds and then another 10 pounds to renew the reservation. We bought a one way ticket on KLM which was quite cheap and defintely under 400 pounds.
The ticket was an E ticket which i checked was geinue etc by checking on KLM's website once it was bought.
