Using SQ Miles to Upgrade UA Tix?

[mister__big]

Pardon if this has been posted somewhere before; I did a search but couldn't find what I was looking for.

If I buy an United ticket, can I use my SQ miles to upgrade my UA seat from Y to J? On the UA website it appears as if this can be done but the wording is ambiguous so I wanted to make sure before I booked.

[9V-JKL]

Yes but only if its booked in Y or B fares.

[mister__big]

Thanks 9V-JKL!

[TerryK]

Y/B ares are very high, you are better off booking Z (international) or A (domestic) class tickets.