--new-instance does not work when old instance is not running

[szeiger]

Even with --new-instance the old instance will be reused if it's not currently running. The flag only works when the old instance is already running.

[szeiger]

To add to this problem: Reconnecting to a devbox (using the already running syncer, e.g. after a network outage) that was started with --new-instance will shut down the current instance and create a new one.