Unable to Use points
 

I travel to Cancun late Nov. every year. Joined early returns and used cards to get miles. Frontier never seems to have any seats available and hasn't even opened schedule for after Sept. 30:(:(

Welcome to Flyertalk!

Frontier's calendar is currently extended through January 4, 2016 for all routes and all seats are available to use points on, although it may be at a higher level. If you're trying to look up flights to CUN and nothing is coming up after September 30 then its because service from your airport to/from CUN has been suspended/cancelled or if a connection is required, then there is a schedule change after that date that makes a same day connection impossible.

I certainly understand your frustration. Schedules changes tend to throw a wrench into plans regardless of the airline.

Let us know what your departure airport is and maybe we can help find an alternative.