When using ControlMaster and ControlPath for bastion connections when I resume from sleep Core Tunnels shows my connections as green and up but using said connections fails.
Taking a look with cmc shows that the connection is stale:
WARNING: Stale ControlMaster connection socket
Removing: /Users/xxxxx/.ssh/sockets/user@hostname.fqdn.com-22
Manually disconnecting and reconnecting the tunnel fixes the issue, but it's manual not automatic. Better handling for stale connections upon resume from sleep would be nice.