If your order says it will be delivered the 24th, it will be delivered the 24th. Updates for launch phones are always pretty delayed.
For example, my order for both iPhones says Delivery the 24th. The order itself has been on Preparing to Ship since I ordered the phones. But I have a UPS My Choice account and our phones actually left China on the 19th and will arrive in Louisville, KY later tonight. The order at Apple hasn't updated, but the phones are still on their way.
Be patient. They'll come when promised.