Originally Posted by
MSPeconomist
I'm surprised that you can (try to) use the same RUC for C+ and then for a second "upgrade" to FC. I know that for GUCs, if you use one for the PS upgrade, it's considered used and cannot also be used to go from PS to D1 when O class upgrade inventory later becomes available. [However, I wonder whether this would work if the ticket hadn't yet been reissued into PS.]
To clarify I used the RUC at the gate for either FC or C+ as the normal C+ automatic upgrade at booking was full due to the last minute booking. I was number 1 on both upgrade lists and I agreed to burn the certificate even if F was full since it was going to expire soon. So at the gate I was either going to go from MC to C+ or from MC to F.