Inside the Event Hub you can update the Start Time for an Event.
Change Event Start Time
(a) Inside of the Event Hub, toward the top of the Event Management Panel, locate and click the ‘Options Menu’. This will open the Options drop-down menu
(b) Click the ‘Change Start Time’ option. This will open the Start Time panel on your screen.
(c) In the Start Time panel, click the ‘Start Time’ selector. This will open a Date & Time selector.
(d) In the Date & Time Selector, select the day and time that you would like to set the Start Time for, then click the green check mark to confirm your selection.
(e) Once you confirm, click ‘Save Changes’. This will post an update indicating the Start Time was updated in the Event Timeline.