appeal

[Gmoore]

Runners on 2nd and 3rd with 1 out. Pop fly to left, runners tag, runner on third scores, other runner stays at 2nd. Following a time out to clean the plate, pitcher comes set, steps off to appeal to third and overthrows 3B. While third baseman retrieves the ball, runner advances from 2nd to 3rd. After retrieving the ball, 3rd baseman walks over and steps on third (other runner is there now). Runner from third did indeed leave early and was called out by the umpire. Is this correct? Should the appeal be disallowed because of the overthrow? What if there was no one on the bases when the overthrow occurred?

I dont think the D lost the right to appeal but what about the runner advancing? If the Pitcher just stepped off the ball is still live correct?