Originally Posted by JonNYC
Well, there ya' go. On some routes there are -B- fares, on some there aren't. There's not much reason to seek one out in your case.
If work sends me on transcons, the only domestics I upgrade using miles, and will buy coach tix, then it's worth considering. At that point, the miles spent on the upgrade don't outnumber the the miles earned (when I get my PLT back). And, I can't always get YUPs (and would feel guilty doing it if B fares are available).