Looks like a sub for the usual B763 flight AA145 JFK-SAN. If it operates in place of AA160 SAN-JFK tomorrow morning, I will try to get a picture of it @ FL120. If its a charter, hopefully another SAN spotter (most likely planespotter3) will be able to catch it.
The AA 763 that was already here departed for LAX last night using a ferry flight number. The AA 762 that got here last night is departing in about 40 minutes as AA9220. I searched all AA 762 tail #'s and didn’t find one operating AA9220.
As a side note for anybody reading this discussion that is not familiar with SAN, AA 763’s are an almost daily sight at SAN, it is the AA 762’s that generate some extra interest when they are down here.
Edit: AA9220