Russ's description of the upgrade order is exactly what we've all known to be the upgrade order for EUA:

1. Status tier
2. Fare class
3. Time of ticketing

Battlefields are a different story. The FT consensus (which has never been confirmed, but seems to comport with most FTers' experience according to the above-linked threads) is that NW battlefield UGs are given out according to

1. Status tier
2. Time of checkin