Originally Posted by
donotblink
Book a return ticket on another airline that doesn't have change fees as a security blanket, 24 hours before your return, try to book on Frontier, and if you can, use the funds from the other ticket towards your next return.
While that could work, since you are booking a return ticket at the last minute, doesn't that likely eat up any savings from the "free" outbound ticket?
Maybe for this to work, you have to book both legs in advance at cheap, non-fee-charge rates, then "try" to replace with "free" Frontiers seats.