Originally Posted by
TravelerMSY
All of this makes sense. An airline can't generally make ticketed changes to a trip plated on another airlines stock, except under certain circumstances around irregular ops. But standby on the same routing doesn't require a ticketed change, since the origin/destination/connections are fhe same.
I think it's an issue of having access to change the pnr vs. the underlying ticket.
In the case of
oneworld carriers, they can technically all accept each other's stock for voluntary changes on revenue tickets, but as a practical matter may decline if they don't have access to the PNR. That being said, BA Avios award tickets are nonendorsable.