Came accross this through some net surfing. Apparently you will receive information from Sprint if you are eligible for this promotion, but if you don't hear from them it wouldn't hurt to call and see what they will do for you.
Sprint Customer Retention Promo Offering up to a $100 Discount for Eligible Customers Sprintfeed
Sprint Customer Retention Promo Offering up to a $100 Discount for Eligible Customers Sprintfeed