Sprint has updated their message to say the following:
"Thanks for ordering the HTC One Silver with White accent. Pre-orders placed through 4/16 are expected to deliver on or around Friday, 4/19. Any orders placed on 4/17 or later will deliver in 2 to 5 business days from order date. You may continue to track status of your order on Sprint | Check Your Order Status
. Since we are processing so many pre-orders so quickly, your tracking number takes a little longer to get to you than normal. Do not worry. If you ordered before 4/16, your tracking email may come as late as Friday, 4/19 when your phone is already on its way to your door. Thanks for your patience."