Content Dripping: Any Further Details?

In the Membership description it reads:

"Want to provide “drip content”? No problem."

However, this doesn't seem to be elaborated upon anywhere. Nor do I find any mention of it in the dashboard.

Is this simply referring to, for example, assigning Membership categories to posts that are scheduled through Wordpress, or is there some inherent 'content dripping' functionality in Membership? If it's the former, that would be rather limited, as this kind of dripping can only be date-based, as opposed to, say, 'first day of sign-up'.