This answer refers to dripped content in the Nanacast hosted membership content area.
In both cases, the content available to them will be based on their “Date Added” in comparison to the “Send on Day #” for each episode.
Reactivation of a paused client will result in the content for the current number of days from the “date added” to be available. So in addition to reactivating the client, you should adjust the “Effective Start Date” field in that client record. This will override the Date Added, and cause the content to be based on that date instead of the Date Added. So if you want them to only have day 60 content after 6 months, you’d need to set the effective start date to 60 days ago.
For the second case, when they register again, a new client record is created with a new date added. In this case, you would set the effective start date back to a date that represents 90 days ago in order for them to get access to day 90 content.