EJM is privately owned aircraft either charter or fully managed by EJM. Some use the callsign Jetspeed, some do not - especially on the charter managed side where they may elect to use Jetspeed on charters or might not. I never did because I wasn't used to listening to "Jetspeed..." and I'd miss the calls. Jetspeed couldn't, at least a few years ago, be used internationally. It was domestic use only and you filed under your N number for those charters.