Yeah, does look like air is up. I ran into a surprise booking Grand Canyon hotels for that week - all in the park full for our 2 nights desired. Could be a big year for spring break travel.
Clearing cookies is worthless anymore as the airlines now have devious programs to identify your computer and shopping by the browser you use, computer make & model, extensions; they are up with the CIA on this I tell ya. I can find articles if you'd like but just don't shop on an airline site. Shopping sites like Kayak.com/Sidestep.com have no reason to want to charge more as they don't get commissions, and I don't think Orbitz does - but Orbitz cannot book American now and Expedia is boycotting AA last I heard.
The best I see ATL-CZM, 3/12-22: $590 on AA, and that requires an overnight on return. Gawd I hate those! I also see $633 using USAir and one channel jump on AeroMexico - 6 hours going, 11-1/2 returning, yuck! And I did check other dates too.
Funny, you can drive to Chattanooga and take Delta for $411 & up, connecting ATL, 4-1/2 hrs going, 9-1/4 returning plus driving.
Spirit ATL to Cancun for $282 is possible, but for your dates it is $406. Must be the spring break crowd. Gawd $792 if you wanted to come back on the 19th - yeah, spring break.
Looking at air and hotel packages for one, wow - I've never seen Fiesta A that high. Other nice hotels for less anyway; other hotels I personally like for a lot less.
Yeah, you're screwed huh?