I read somewhere, I think TPG, that actual sales of PE are in effect for 1/15/18 flights. If available before then, they will be assigned as the 789 were. I have one mid Feb where I had an EF notification yesterday and noted that the computer had correctly reassigned us from 7G&H to the new bulkhead 9G&H.
eta Source:
https://thepointsguy.com/2017/07/aa-...rofit-details/