Pros
Flight benefits were fun. I was able to take several trips and never had a hard time getting on a flight via standby. The airline industry is very interesting, and by extension the work in FP&A at an airline can be very interesting. The company has a lot of difficult decisions to make, and relies to varying degrees on finance in making many those decisions. The work is generally engaging, so you likely will not get "bored" FP&A team is talented.
Cons
The group is unnecessarily high strung. The building always seems to be on fire, and certain leaders within the group have very short tempers in dealing with analysts. Prepare to be yelled at if you make a footnote (non-numeric) error, and your job may be in jeopardy if that footnote error is seen by a VP or above. If you are not happy in a work environment that can only be described as "intense", this is not the place for you. You should expect to work longer hours in this group. My manager stayed until around 7pm on average. Although this was above average for the group, it was very rare for me to get out prior to 6pm on a Mon-Thur. Hours were of course long at every quarter end, but that is to be expected anywhere in FP&A. Promotions at Frontier (and especially in finance) are somewhat rare. They almost exclusively result from a vacated seat above you. Not uncommon to see a high performing analyst in the same role for 2+ years without being promoted to the next level (e.g. from Analyst 1 to Analyst 2 to Senior Analyst). Many leave prior to being "in the right place at the right time". Pay is below market. PTO is only 10 days per year. My experience overall at Frontier was mostly negative, primarily driven by the overly intense atmosphere. While I likely would have felt "up for the challenge" prior to starting this job, it is easy to get burned out from an intense and confrontational environment when you know that there are higher paying opportunities elsewhere that cause less anxiety and require fewer hours.