It takes several months for Apple to sell a refurbished version of a newly released product. Because refurbs are new devices that get sent back, it may take 3 to 4 months for them to become available. For very popular releases, it could take 6 to 9 months for devices to hit the refurbisher's shelves. Some independent refurbishers may stock refurbished products a little earlier than the Apple Store.
If you are looking to buy a newly launched Apple product as a refurb, be prepared to wait three to six months for it to arrive on the refurbished market. Great refurb deals come to those who wait.