Hi all, we have (1) a package where customers pay for it once, and along the year they'd get 12 or 24 products delivered to them as it comes out. (2) They also get an additional discount on all other product variants linked to this 24 products. 

Is there an app to manage this day-to-day? Priority towards (1), (2) would be nice to have.

Otherwise, what would be a good workflow to manage this?