With first-class monetization, I've got more itineraries with RPU/GPUs applied that have only cleared one of multiple segments. I am wondering whether UA's upgrade algorithms give more (or less) priority to clearing waitlisted space when a GPU/RPU has already cleared connecting flights in the itinerary? Or is each segment assessed independently?

As a concrete example, I've burned one RPU for a DCA-ORD-SFO-YVR itinerary next January. The DCA-ORD leg cleared at ticketing, but the ORD-SFO and SFO-YVR legs remain waitlisted. Under the rules, if I don't clear upgrades I'll still have used the RPU for the shortest leg on the trip (on an E175 to boot).