In brief: Events are easily edited after they have been created.
Login using your credentials at login.eztix.com
Click "Events" in the main header, displaying a list of your upcoming events or tours by date.
Locate the tour and date in the list.
Click the blue "edit/manage" link to the right of the date you wish to edit
Alter the fields to reflect the changes you are looking to make.
Click "Save" at the top right or bottom right of the "Event Details" pane.
Tour Operator FAQ:
Q: Will these changes affect my Templates?
A: No, only the specific instance you have chosen to edit.
Q: Will future template changes override any changes I make?
A: No. The fields you have edited will no longer be affected by template edits. Only those fields still mirroring the template would be changed.