Thanks Richard. I read all terms and conditions carefully and it really seems like it is not excluded.

It specifically says "S" (even V,W,K,L,T) is allowed.

Under "Restricted Fares" it covers specifically, these types: - Industry (G class), companion, bulk, convention, tour conductor, contract, children, family plan, government, group, military, student, tour basing, RTW, circle Pacific, and Visit USA.

Not much they left out there, but 'non-published' are not among them!

Under "Ticketing Instructions"

Has a note on back under "Ticketing Instructions" saying:

" Agencies - see S*PMA/Dollar-UA Systemwide
Treat as type "B" voucher
Use ticket designator on front of voucher (IPW$$$)
See ARC Handbook for instructions "

It says under "Ticketing"

You may redeem this voucher by calling United Airlines or your travel professional.