The Registrar's Office understands that many new faculty are hired in late July/early August (and sometimes right before classes start).
This is most problematic for the fall term because students register in April. Since you need the instructor's name posted on Yale Course Search (YCS) in order for the Canvas site to open, many departments list the DUS as the instructor and include a note (under Section Text in WEN), to the effect that there will be an instructor new to Yale teaching the class and that YCS will be updated with the instructor's name closer to the start of term.
The Registrar's Office needs to create an instructor record for new faculty. This requires the NetID of the new instructor; a record cannot be created without one. Once your new instructor has their NetID, email the information to email@example.com. Depending on volume, this task could take a few days. Someone will let you know once the instructor record has been created and you will be able to add the new instructor in WEN the following day. At that time, remove the name of the DUS.