Originally Posted by
coolcoil
You are correct, but I was talking about going all the way from EZE to ORD on one RPU.
You could use an RPU on UA for PTY-IAH-ORD. However, if you tried to use it for the full routing EZE-PTY-IAH-ORD you will get shot down. The UA reservation system will see that as a deep South America routing and require a GPU. This would be true even if you book through COPA with codeshares.
I still maintain that this is incorrect. RPUs are valid for EZE-PTY and PTY-anywhere. The online system might choke on it but an agent should be able to push it through without issue.