With Subscribers, you can create a recurring notification that allows you to subsequently send a push notification automatically. (Please note that this feature is currently available on the Shopify eCommerce platform only)

To set up a recurring notification, log in to your Subscribers.com account dashboard and navigate under "Ecommerce"> Recurring Notification menu.

Now you'll be redirected to the page where you'll be creating your recurring notification which is really straight-forward.