CN sends notifications to the user email that is associated with the CN account. The frequency of each type of notification can be adjusted following these three steps:
STEP1: Open the left menu and select "Email Notification".
STEP2: Modify the frequency of each notification to what you prefer. There are four options: Immediately, Daily, Weekly and Never.
Note: the Every 4 hours was removed in August 2018. Items that had this frequency were set to Daily.
SETP3: Once done, remember to click SAVE ALL at the bottom of the table.