Courier 2 (2.6) has a new "Transfer" drop down. I understand what "Select items and all dependencies" and "Selected items only" means. But the other three options with the dependency levels has no explanation anywhere that I can see. I even tried watching the "Watch video on how to deploy" video, but as it seems to be for a previous version, it doesn't explain at all. I couldn't find any user guide anywhere either. Can anyone tell me what is considered level 1, what is level 2, and what is level 3?

Thanks!