I forgot to Stop the Edge 500 after a ride. So it was running while the bike was in the car on the freeway. I figured out editing max speed, distance on Garmin Express but I couldn't edit average speed. Why not? It didn't recalculate after the edit in distance and time.
No idea why it didn't recaculate but you could try using fitfiletools.com to strip the part where you were on the freeway out of the file and then delete the original from Connect and upload the modified file in its place.
