Originally Posted by
jsloan
I think it's possible, in the same way that it's possible to cut a suburban lawn with scissors, but finding someone with the requisite skill and willingness to try is a crapshoot at best.
I actually don't think it's possible. The ticket is priced RT to SIN. You can't retroactively create a fare break.
The realistic options are:
1. Call UA and ask how much to refare to W (and see if they'll waive change fee);
2. See if it's possible to upfare to P;
3. Do a miles + cash upgrade for the NRT-SFO segment.