I called UA in the end and it turns out I had an aisle seat already assigned. However I always fly in window seats so I asked the agent if she could asign me another seat. She suggested I call bmi but then told me they would probably just refer me back to UA After a bit of pressing she said she could put a request for my desired seat so I gave her a seat number, and she said the request had been noted. What exactly does this mean? A week later I just checked the bmi website by doing a dummy booking and my requested seat is not occupied.

Has anybody had any success getting a pre assigned seat on BD long haul when booked as a UA flight?