No, that isn't possible. With DPS 2015, you can create two types of subscriptions for iOS apps: Standard and All Access. With a Standard subscription, users are entitled to collections in which the availability date falls between the subscription start date and end date, and users are not entitled to any content published before or after their subscription duration. With an All Access subscription, users are entitled to all content in the app regardless of availability date. When the All Access subscription ends, users are no longer entitled to retail content (similar to a music or video service). There is no way to use either type of subscription to entitle users to only some retail content. You would need to set up a direct entitlement server to do something like that, but you're likely better off creating separate apps.
