Thanks for all the responses. So it sounds like I need to book our tickets separately if I want to book the cheapest fares (to save money) for any chance of upgrading, because she would be ineligible for a companion upgrade on a (T) flight. Is that right? Otherwise the system considers us a single item, and since she's not allowed to move up, I won't either. (Yes, I would abandon her in coach. She sleeps the whole flight anyway.
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