Yup.
Book 5: pay for four, get one free
Book 6: pay for four, get two free
Book 7: pay for four, get three free
Book 8: pay for five, get three free
Book 9: pay for six, get three free
Book 10: pay for seven, get three free
Over 10, out of luck or split your reservations.
We're doing the 9 days and still saving over $1000. Hoping for a 40% discount though because I think that will be better for us. So far no luck, so I don't think it will happen. However, any discount is better than no discount.