Project Admins can manage notifications preferences under the tab Project Details - Notifications. You will see the screen below appear.
By default, Daily summaries are sent at 4pm based on the project's time zone. Weekly Summaries are sent on Fridays at 4:30pm based on the project's time zone. Admins can edit a project's timezone via Project Details - Settings.
In the event you would like to unsubscribe, scroll down to the bottom of a Daily or Weekly Summary email and click on the blue 'UNSUBSCRIBE' button. Tapping this button will take you to a screen where you can manage which project(s) daily or weekly summaries to receive.
Click here to learn more about Notifications