Virgin is dropping or suspending PHL. When Virgin first added PHL, it made the majors led by US lower prices on the LAX and SFO transcons. VX also offered connections out to other west markets like SEA and SAN.

That additional competition I believe did hurt Frontier originally in its connection efforts on PHL-DEN, as the connection market to the west coast diminished as flying a nonstop became more affordable. Virgin began in April 2012, and Frontier pulled out of PHL-DEN later that year. But that's just my theory.

It's going to be more expensive to fly nonstop to the West after Virgin leaves as fares were higher prior. Some passengers might be more inclined to travel up to EWR or will fly Southwest with a connection.

Will Frontier be more inclined to find a way to link TTN and/or ILG to the west coast, including ensuring ILG-DEN schedule is timed correctly for west connections and other strategies (maybe other TTN one-stops, ILG-LAX/SFO like 3-4x weekly each)? Let's hope.