My flight is direct too. I was on my older PC and the browser pulled up the calendar search and that's how I saw it with all the days 'laid' out with price.
I also checked CO for my date range, $700ish + a lot more travel time and scopolamina parties galore
I wanted to be in Puebla (for the honies) early last week then CDMX later in the week for EDC Mexico but had to stay back in Austin to get some work done on the home. There is a decent MEX airline that has short non-stops twice daily from SAT to its home base in MTY then connections onwards to many places in MEX however when I saw the SWA fare I'm going back to CR! I booked 8 nights at La Amistad.