resurrecting this thread rather than start a new one:

Flying SFO-TPE // TPE-NRT // KIX-TPE-SFO next year, booked with DL SkyPesos. TPE-NRT in economy and the rest in biz, all on CI. I obtained the CI PNRs from Delta Twitter so I could select seats.

For the TPE-NRT leg we were banished to row 56. Then I remembered that mom is DFP Gold and switched her info in the CI reservation. This opened up seating as far as row 34, but it wouldn't stick. It seemed like the web site was willing to let her sit there but not me. I called CI and I'm not quite sure I understood what the phone agent was saying but she seemed to think that it would work via the web site if we'd booked individually but not since we were on the same reservation. Anyway she had no problem moving us to row 34. It's still not clear to me whether I as DL DM/STE+ should have access to these seats on my own.

The J awards are booked in O and the Y award in X. It's also not clear to me whether the award X is the same as the same X mentioned on the Earn Miles page that is part of the L/X/G/S seat selection exclusion, because the same page doesn't mention O at all (but the Ticket Awards page does).

Anyway my is mostly academic/rhetorical since I got seats 20+ rows forward