In duels, you have to hit the guess button to send a guess, you can't simply have your marker on the map when time runs out. But I think in live challenge, you can simply have the marker on the map when time is up. Why can't duels be the same?
Part of the reason I'm suggesting this is because there seems to be a bug where once in awhile, when I hit the guess button, the button grays out and just spins forever, and when time is up, my guess doesn't register. So maybe this feature would help with that bug too?