E-6s are stationed at Tinker AFB (the image you used even shows the flight path starting at Tinker since they just took off), so the positioning in this case isn't particularly relevant, unfortunately. The E-3 that was spotted earlier looked like it was heading home and about to land, since they're also based there. You've got a good eye, but don't forget to keep in mind where our own forces are stationed so you don't bite off on something mundane or ordinary.