Overnight Flight? DCA-PDX through DEN
 

Rare Frontier Flyer here and just want advice. I would like to fly DCA-PDX connecting in DEN. While I see there are flights that would connect perfectly, the same day,
the only schedule they offer on the day I want to leave is DCA-DEN with an overnight connection in DEN. This makes no sense. I could buy the separate legs-has anyone done this?

This works fine as long as your first flight is on time. If you miss your connection, you will be on your own.

You could try to chat or go to DCA in person and see if they can ticket the itinerary you want, maybe it's an IT issue. I also see some examples of itineraries showing up on flyfrontier.com but not google flights for some reason (e.g. April 15).