The key there is that wherever in its orbit the vehicle is outside US surveillance capability, it may well be able to change its orbit, before the US “Space Fence” picks it up again. That was one possible use of the X-37b itself, because it could dip into the very top of the atmosphere, change orbital plane using its small wings, and recircularise its orbit, all without spending nearly as much propellant as normally is needed for plane change maneuvers, which is *lotsa propellant*.

This sort of activity is yet another argument for a fully global Space Domain Awareness System, instead of just the USAF Space Fence in the Western Pacific.

Surely we have tracked the launch and know exactly where it is in space?