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Upgrades with miles have higher priority. Up until your upgrade window, which is 72 hours before the flight, upgrades clear first on first off, which means whoever requested them first gets the upgrade within the respective waitlists. IOW, if there is confirmable upgrade space you will get it when you book, or anytime up to departure. Once the 1P window opens up it makes no difference how your requested your upgrade. If your upgrade does not clear before you go to departure management upgrades clear by status, fair basis, and time added to the waitlist. So the short answer is yes, you have a better shot with miles.