Only if you configure it to do that. You can use Wants= and After= for your service to start it after the network, but not restart otherwise.
The behaviour you describe is not unreasonable to want: If your network device goes away, what exactly are you binding the socket to? How are you restoring the listening when it comes back up? But it's up to you to say which one you want.
The behaviour you describe is not unreasonable to want: If your network device goes away, what exactly are you binding the socket to? How are you restoring the listening when it comes back up? But it's up to you to say which one you want.