<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by FlyerGoldII:
PS-I guess, if the outgoing flights are with 14 days, the cheapest upgradeable fare is H class fare. If on the same itinerary, the incoming return flights are more than 14 days in advance, can I purchase the return flights on a V class fare basis, instead of H class fares?</font>
Yes, you should be able to mix fare classes provided that you meet the requirements of both fares.
You could also consider UA so you could get E+.