Constrained camera not moving on until frame 157?

I’m trying to get this Earth fly around scene going. Created the Earth from an awesome tutorial, used the clamp to constraint on the camera with the path as the target, used the track to constraint on the camera with an empty (on the eastern seaboard) set as the target. I then increased the number of frames to 500. When I play the scene (rendered below), the camera does not start moving until frame 157, then stops abruptly at 371. I’d like the camera to start moving immediately, then slowly come to a stop at frame 500. Any pointers?

2012_11_12_EarthFlyAround.blend (1.12 MB)

Any pointers?
The biggest thing to point out is you have not attached or linked to your blend file. The only person in the world who knows what exactly your blend file is doing is YOU and you’re the one asking for help. If you want help, please don’t deliberately make it as difficult as possible for those who may want to help you.

Included Blend. I figured it was more of a general question about constraining to a path; didn’t know you’d want to see the entire scene.