Wide availability of this fare, worked nicely into my schedule, so booked over Thanksgiving to visit family down there. Yes the 777 lie flats are not new, and layover in MEX is a little long, but a great fare that books into I class, so credits well to DL.
FYI when looking at Google Flights the calendar did not show great availability, but clicking on my dates anyway brought up the low fare. Bookable at Expedia or directly on Aeromexico.