They used to have a program called "Quick Ascent" but they seem to have got rid of that a couple of years ago.
I'd put together a package of information with your status at other airlines, flights flown and reasons why you'd like to switch to F9 and mail them to:
EarlyReturns
PO Box 17304
Denver, CO 80217-0304
You might also call: 866-26EARLY (866-263-2759) They might give you a fax number.
You can also e-mail:
[email protected]
This information from their web site:
http://www.frontierairlines.com/fron...departments.do