We had an event organizer who accidentally picked the wrong time zone for the shift. So when you add it to your calendar, the shift is different than the event time (see attached screen shot). It appears that the only way to make this update it to remove all participants, which seems ridiculous and a lot of work. We feel the edit should be allowed and then a message is sent to those who are signed up that there is an update. They can elect to stay in the event (with link to download an updated calendar invite) or they can remove themselves from the event (provide direct link to even page where they can do that)