EJI
I'm happy to respond to your question.
One of the things that precludes some companies from buying a fractional share of a Gulfstream is the principals desire to see a familiar face up front in the cockpit. Therefore, EJI offers as a condition of sale the option to allow the purchasing companies pilots to fly the EJI aircraft if they meet all EJI qualification and training requirements and successfully complete the EJI written and flight evaluations, which by the way are quite stringent. Although a FAR Part 91 operator, EJI trains to and generally flies to Part 135 requirements. Actually, EJI does have a Part 135 certificate at Bradley, but they do not routinely use it.
My company paid me, but I performed exactly like an EJI Captain, reporting to Columbus for dispatch and so forth.
Because EJI customers are charged only for occupied flying hours (domestically), not positioning flights, normally, EJI pilots would fly the jet to where my companies trip began, then we would fly the aircraft to our various destinations, leaving it at our final point for EJI pilots to recover.