United Vacations here in the U.S. is a different company than there in the U.K.
Most air-inclusive packages here in the U.S. are booked in bulk or consolodator fare classes.
Here in the U.S. the terms state that upgrades are only permitted on air-inclusive packages that are Domestic United States.
Over there, they plug the following:
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Upgrade to United Business for 20,000 Mileage Plus Miles when booking selected fares from United Vacations.</font>
Here, they tell you if you have any questions about upgradeablity, to contact United Airlines directly.
I would suggest you do the same.
If you do qualify for the lower mileage award, it should take the agent just a few keystrokes to credit your account.
But because sometimes the S or T or B fare basis can mean something completely different outside the U.S. than it does from point of sales here, I really don't know what to tell you other than to call United with your inquiry.
It could be that any United Vacation booked air travel requires 20,000 regardless of the B fare basis.
[This message has been edited by PremEx (edited 03-18-2002).]