The Last Man Standing is a situation that happens when the host needs to close his server since VPN's we use are busy. In this case, no more players can join, and the last remaining players will compete in a death-match to be the "last man standing". Sometimes, players will be disconnected before the death-match ends. It usually lasts 45-60 minutes but can occasionally be longer.
Most of the Last Man Standings will end up disconnecting all of the players still standing, resulting in a total closure of the server, but a few servers may re-open after the death-match and be full of players again.