How do I change the date, time or venue?
Edit the event in Design → Basics and tell guests about any important change.
Open Design → Basics and edit the date, time or place. Check the timezone as well as the displayed time.
Review the guest page after saving. If people have already been invited, send a message from Manage → Messaging explaining the change.
Do not assume an earlier email or a calendar entry a guest already saved will update itself. Include the new details and ask guests to check their calendars.
Updated