Originally Posted by
s0ssos
When you say change to Etihad, you mean just one segment? The answer to that has to be no.
Even if they were together I feel AA books Etihad tickets different, because I had a flight from AUH to SYD, and wanted to add on a segment inside Australia and they said it was additional miles. So not the same as their normal ticket.
The rules change for awards made using non-oneworld partners, so this might invoke redeposit, fees and a new award in AA policy. It may differ from USDM, but the substitution of a non-oneworld segment may create some problems under oneworld award policies (which normally do allow change of oneworld carrier) iirc.
Dave Noble knows this stuff better than I, so it's good he's reading this thread and can correct me.