Subscriber IDs are created when a user opts in to your website. They are kept and stored in several manners within Aimtell (both client-side and server-side).
Every time a subscriber visits your site, their subscriber ID is stored as a cookie for 100 days. Upon subsequent visits, this 100 days is extended.
What happens if a user clears their cookies?
If someone revisits your site who has previously opted into your push notifications they do not have to subscribe again. Aimtell will automatically re-add or update them as a subscriber in your account without needing to show them your opt-in prompt again.
In an instance like this, when a subscriber clears their cookies, Aimtell instantly checks their existing push permissions, and if they have previously granted your site permissions, we will look up the corresponding subscriber ID on our server.
Note: While Aimtell has several mechanisms to restore the subscriber ID, push subscribers are designed to be inherently anonymous. This can potentially lead to instances where if you force clear everything (including the service worker), both the cookies would be gone and the subscription would change, making it nearly impossible to guarantee subscriber ID reassociation 100% of the time. In rare cases like this, a new subscriber is associated and the old one is marked for deletion and removed so that you are not billed for an "inactive" subscriber.