Stock is up 5%, I think it'll adjust after the street and analysts digest the data.
Looks like EPS exceeded expectations, costs were down, total revenue missed, and PRASM is down from last year. The PRASM and Mr. Fornaro's warning about yields may affect the stock price going forward. If it wasn't for the decrease in costs, I think the stock would be in much trouble.
Update: looks like the street is starting to digest the TRASM (as Spirit reports it) decline. The stock is now up only 2%.
Spirit Airlines Reports Second Quarter 2016 Results (NASDAQ:SAVE)