Interestingly enough, Delta announced that they are flying their lie flat 757 from JFK to SNA. And once AA is rid of their A321T, since they only have the XLR to replace a premium configuration, it will be too heavy to operate out of SNA (unless they block seats). So will AA pull out of SNA in the near future because they don’t have the proper aircraft? Or will stay in albeit with blocked seats.
And I think EWR-SNA is one of the candidate routes for United’s Coastliner.