(from Melbourne, sorry for little time on webflyer, Hingis keeps me busy watching her)
sorry CatMan, no upgrade internationally on those cheapest UA fares. (may be you can change the ticket to a upgradable fare by paying a reasonable difference? - but may be this could/would your business relationships?).
yes, UA gave up C/Class from Westcoast to Honolulu: but at least they allowed one-way upgrades, using 8'000 miles/passanger (I had to change for a later flight LAX/HNL on that nov-4 for this).