Doesn't matter who you work for, you are taking a huge risk abusing the sick call system to attend these events. My advice has always been that if you have to call in sick then do not do anything that can be easily traceable by your employer such as using your CASS credentials either through KCM or jumpseating. Otherwise the company has justification for disciplinary action or even worse termination and there is nothing the Union can do about it.

With that being said, Frontier actually pulling the attendance records and crosschecking it seems a little extreme. But in the last few weeks Spirit and Frontier have shown themselves to be very hostile to their pilot groups. So nothing surprises me anymore, get out while you can.