Does CO frequently zero-out R class availability precisely when EUA runs for a flight, and then quickly reinstate the R availability, effectively "skipping" that run of EUA? I understand upgrades can only occur through EUA when R class is available at the moment that the EUA batch process is run. I understand that for plats EUA is run (among other times) at 120 hours before the flight (5 x 24 hour periods). Looking at a flight IAH-DEN for next Saturday, I made the following observations: T-122 hours: 8+ R-class seats available (observed through dummy-booking of OnePass reward upgrade for 8 passengers through continental.com) T-117 hous: 8+ R-class seats available. My upgrade did not clear between these times. As a point of reference, a previous flight on this same itinerary did clear at T-120 hours (for that flight) (also with "standing" R-class availability) indicating that I am properly recognized as an elite in the system.