Originally Posted by nikolask

A data point that not sure if super helpful: on my flight last week, during boarding, two passengers in row 3 (Economy) kept mentioning to the cabin crew that they had an upgrade cleared but were still sat in Economy. Meanwhile the cabin crew were trying to find out if this was processed or not but they weren't able to confirm that. The purser went back to the two gentlemen and explained that they weren't seeing a confirmed (voucher) upgrade but only an upgrade of a row in Economy further back to row 3 though the two passengers still insisted on the Business Class upgrade. Apparently in the end, they were told 'there are still two empty seats in Business Class so you can take them' and they were moved forward after boarding has finished.

I wasn't convinced how legit that was but it seems that the purser might be able to process or look into the status of an upgrade while onboard. I'm pretty sure though that by the way this whole situation was handled, this was a gesture of good will by the purser rather than the two passengers using their upgrade coupons...