It could be set now. It doesn't matter. Almost no one flies his own jet. Jet planes require a ton of money, and employees to operate and maintain. You can't just fly the things once in a while when you feel like it. You can't even just fly a simple single engine plane once in a while when you feel like it. You have to be "current" which for most people means doing a lot of non-productive flying, particularly if one is instrument rated. (And if one is not instrument rated in an area with weather such as we have near NYC, one can't really depend on being able to fly when one wants to go someplace, especially someplace far away.)
ML/NJ
I have friends in the business, so I am aware of how that operates (both corporate and leased). I think that the protagonists could be expected to own the efficient means and keep them operational, especially if they are in a corporate pool