Xbox Game pass 1 month – $3.89 (cdkeys) stackable?

Just came across while browsing cdkeys’ site. $ 3.89 for one month of xbox gamepass. It appears you can buy multiple quantities so I’m assuming that this is stackable. Please feel free to comment and correct me if my assumption is incorrect. $ 3.89 x 12 = $ 46.68, besting the current deal here in SD of $ 69.99.

https://www.cdkeys.com/xbox-live/…ox-one-360