In most cases, alerts are sent immediately. There is the flexibility to change this setting send emails instead at different times which may be more convenient for users.
The default setting is usually appropriate, but it may help to control when users receive alerts if emails are likely to be ignored or discarded when received outside of a normal work schedule.
For high volumes of alerts, the Summary Mode helps by consolidating alerts into a single email.
9/8/2015 9:13 PM