I hope I am wrong but let me just ask... So, you created this great functionality where you store all contacts in a beautiful table with all kinds of valuable properties. Then you even gave us a useful filtered view of those contacts who have "subscribed" to email marketing. You even included 'language' as a programmable property (via API), which is not even editable from the admin UI apparently. But, your API doesn't afford us read or write access of the "subscription status" property (whether a contact is either 'subscription not set', 'subscribed', 'unsubscribed')? From what I can see, THE ONLY ways to modify this useful property are 1) via a 'Get Subscribers' form submission or 2) then manual editing of the contact by an admin. There is no way to modify this property programmatically. I hope I got something wrong. Please educate me if so. If not, imho,....wow, major omission.