Ability to Modify Calendar Appointments Scheduled by Inactive Staff Member

Currently we schedule SOLs, Deadlines, and Court Hearings/Trials on the calendar, however we are calendaring things 1-2 yrs out. If that deadline or court hearing changes and the person that scheduled it no longer works here, we are unable to modify that appointment/deadline even though everyone has calendar permssions and everyone is an owner. The only option I was given by Needles Neos is to delete the old appt and make a new one. Which is crazy when you think about how many deadlines and things are on the calendar on a daily basis.