There are instances when we need to change the date/time of a live training session (sometimes just moving it forward or back by 30 min.). There's no way to notify the attendees that are already enrolled that they need to update their calendar invite. On some occasions, I've just emailed the attendees and told them to move the calendar invite themselves. Other times, I've cancelled the session and recreated a new one 30 min later. But then the attendees need to re-register.
When a session with attendees has a change to the date, time, location, or online meeting link (maybe other details), it would be helpful if there was an automatic notification with wording something like this:
The [live training name] session that you registered for has some updated details. Please add this new invitation to your calendar and delete the old invitation. If the updated session does not fit your schedule, please register for a new session (link to registration page).