Yes, it is feasible for visitors to notify staff if they will be arriving late, but only if the visitors generate tickets by scanning a QR code. For that, you have to enable the settings:
Go to the "Settings".
Click on the "Account Settings".
Click on the "Ticket Screen Settings".
4. Enable the “Late Coming Feature”.
5. Click on "Save Changes".
Now, visitors can select the option to notify the staff that they are running late.