In need of some tier points to requalify for Silver with reduced number of points, I was hoping to do a return trip to JER. Managed to pay for an upgrade on the outbound leg, but the return leg is showing that I "cannot upgrade this leg". Could anyone kindly shed some light as to why this might be? Is it a matter of trying to upgrade the return leg on the day of the flight or is there some way it can be done at the airport?
TIA all!