When a document is due on a certain date, are there reminders that are automatically sent to remind them from the Ostendio platform?

If a document is due as in expiration, owners of the document are notified of expiry. These two articles should help:

1.     https://knowledge.ostendio.com/knowledge/do-i-get-a-notification-when-a-document-is-set-to-expire

2.     https://knowledge.ostendio.com/knowledge/why-did-i-get-a-notification-of-a-task-due-many-days-out