There's an interesting article as a follow-up to that.

http://www.delawareonline.com/story/...ware/11527625/

"Frontier Airlines shows staying power in Delaware

Marking its first anniversary of Frontier Airlines service, New Castle Airport Director Stephen Williams said the year has both demonstrated the viability of the airport for commercial air service, and allowed it the chance to collect data on customer patterns that might help someday find a second airline that would be a good fit."

It's quite comprehensive, and with the sensible proviso that Frontier's schedule isn't for everyone, business travellers, eg.

The most requested service seems to be all Florida:

"Williams said the airport wants to see more Frontier flights, and more destinations with more frequency. Customers are saying they want more flights to Orlando, as well as service to West Palm Beach and Fort Lauderdale, Florida, he said."

Since PHL-JAX is over 500 pax per day, I wonder - again - if ILG-UST would work?