I Purchased a CO ticket for my mother on United.com to use an ecert that was expiring. There are no "free" seats available for seat assignments on any of the legs of this roundtrip from RSW to SNA via IAH.

I then transferred 32,500 miles from my United Account to my OnePass Acct (Plat) to upgrade her to First Class. The short segments cleared (RSW-IAH and IAH-RSW) but the she is wait listed on the longer segments to/from SNA. The flight to SNA looks pretty good (flying midweek and only 4/16 taken) while the flight from SNA is not quite as good (flying on Saturday but 7/12 taken).

Will CO allow me to get ELR seats in the event the upgrade to F doesn't clear on one of these legs (guessing no)? If not, will there be a partial refund of miles for the uncleared segments (I am thinking no)?

Thanks