Just got off the phone with our Aegean Air friends in Greece...I clarified what the minimum miles factor meant.
It means - flight distance. e.g
LAX-SFO in G = 337 mile flight = no credit at all not even 50% (appx. 168 miles) for G
LAX-SLC in G = 589 mile flight = 50% credit for G = 295 miles
US Air has no mile flight minimums and virtually all fare codes are good with the exception of three, O, I and X - IIRC.
Is this fare code from US the letter U or X? "UXAVNL6P"
Hope this helps!
TIA!