To temporarily override the content on one or more displays in Appspace, the Broadcast feature is used. The most common use of this feature is overriding a display for a day to show special content for an event.
To set up a single-day, single-display broadcast:
NOTE: Pressing the "Activate" button will cause the broadcast to immediately show on your selected device(s). There is no need to use the button if you set a Start and End time via the schedule.
Further reading: Configure and Manage Broadcasts