I heard that the airports must meet some kind of minimum threshold of airline service. But I would imagine Flexjet didn't look into every single airport in the US served by the airlines. It could be worth reaching out to the appropriate people to see if your particular desired airport could be investigated to see if it meets the criteria. I may do this with one or two airports, both of which are on Netjets list of domiciles. Given that, so far, Flexjet has been very flexible with case by case travel arrangements for training, I'd be surprised if they flat out denied any requests for new domiciles before taking a look at the requested airport. Seems like it could be a very easy way to potentially keep a pilot and attract additional pilots.