The priority can vary depending on who's actioning it and whether they follow 'the book'.
I have come posts with across several variances to 'the book'. One is:
- Qantas Chairman's Lounge
- QF WP
- o/w Emerald
- QF SG
- o/w Sapphire
- QF PS
- o/w Ruby
- QF QP
- QF NB
- Others ...
I don't believe Qantas have historically employed Fare Class, this may be changing - I don't know. As a QF WP I have been upgraded on O class flights a few times.