I have a £999 fare which was for the 747's retirement. It turns out I can only fly one way as of now and need to change the return. Does anyone know if this will be possible without paying a fare difference? It's a flight to MLE and the fares are around £4,000 return now. I have had a cancellation last week and they rebooked me onto QR for the return. I want to move this to a few months later.