I have 2 main reasons for needing a delayed start or due date or an individual basis. We auto enroll new accounts in the training and it is ongoing allowing for completion after the due date.
1: Our company with global employees has several different ways of handling start dates. Sometimes an ID is created months in advanced and sometimes a week in advanced, we have 25 different regions, managing all of that with a 1 week delay before sending an "enrollment as a notification not an actual enrollment email" as some suggestions have been made doesn't work most of the time, it's just delaying the inevitable frustrated manager. We have already extended the enrollment Due dates but with employees starting all the time at different times I get many messages from Managers that they haven't even started yet or just started a few days before the due date.
2: Supporting regions/states where they have extended medical leave or maternity leave has us trying to figure out a way to not repeatedly notify the manager (they email us every time with the same information) while someone is out for months or a year at a time. To be able to set someone as on Medical or have the due date moved would be a big help and cut down on tickets.