Having worked for EE previously, and in supply chain at other networks I can assure you the way the OP described the 'allocation' process as working for the carriers simply isn't true. Allocation negotiations go on for months prior to the phones even being released, there isn't someone sat there waiting to press the button on order the day after it's announced or something.
Also, typically, the smaller the network/retailer the less allocation naturally. That is why when the iPhone 5 was released, Carphone Warehouse were selling a model that didn't work with 4G. They bought the stock from a reseller, as Apple wouldn't deal with them directly at the time.
