We definitely have cases in which we need to change dates when people are already signed-up. Things happen in "Real-Life" such as trainers getting sick or other circumstances that call for changing dates of training.
I don't really see the point of "Locking" session dates when someone signed up - if you don't want to do it, simply look if people are already booked and don't change the dates then...
At the moment the workaround to get the functionality of updating session dates I use is:
- Export the signed-up list to excel.
- Remove users from being signed up - using "Add/Remove attendees" (this sends them the cancellation of dates).
- Change the dates with no one registered.
- Add the users again to the updated session (using the excel list to manually search for user 1 by 1) - this sends them the updated session dates and calender invitations.
Obviously, automating this is much preferred.