The best way to find out if UA is releasing those 40K seats to its partners is to do a search on one of the other *A websites that show partner availability on line. The two that I use are ANA (requires an ANA account) and aeroplan.com (AC's FF program; doesn't require an aeroplan account). If either of these show a partner award on UA, you can probably book it using US miles.

As PHL notes above, UA doesn't always offer the same low mileage awards to its partners that it does to its own members.