You ARE eligible for a discount. Sprint offers upgrade discounts at 1 and 2 year intervals. If you wait until your two year mark, the discount will be greater. Not sure about you being just under the 1 year mark, though.
Either way, in order to get the discount, you need to sign up for a new 2-year contract.
Either way, in order to get the discount, you need to sign up for a new 2-year contract.