Not sure if this is the right thread, but I've noticed something interesting while looking around for R availability on ORD-LHR.
For some reason, it is showing some R availability on the ORD-LHR flight if I take an earlier feeder flight into ORD with a 4hr connection, but R0 on the exact same ORD-LHR flight if I select another feeder flight into ORD.
Why is the feeder flight affecting the R availability on the second flight? Would I be able to book the flight with R0 and call to apply the GPU since that flight technically has some R availability?
Search your legs separately. What you're seeing is very common. It's because the feeder fligth doesn't have R space, while the ORD-LHR does. But if you search them together, it takes the lowest common number between the two.
For example, if LAX-ORD has R1. And ORD-LHR has R9. If you search LAX-LHR (connecting in ORD), you'll see R1 displayed for both legs.
Yes you would, just search the ORD-LHR flight separately to see how many R spaces are available if it's more than you