This morning 3 HK, the official Apple carrier partner, began selling iPhone 3GS in Hong Kong. At the same time Apple Online Store Hong Kong began selling versions without carrier-contracts at a price of HKD5388.00 and HKD6288 respectively.
Now (16;00) Apple has changed their estimate shipping duration from "24 hours" to "5 - 7 business days" for both models of the iPhone 3GS, which is an indication that the iPhone is sold out at their online store.
Similar reports are also coming in from various 3 HK store outlets throughout Hong Kong.
Although, we do not know how many units of either channels had sold but we can be sure that it was at latest more than 5. I bought mine from the Apple Online Store and I have heard from others also done the same. My order is still showing a delivery date of this coming Monday. I presume that means my order was prior to Apple Online Store Hong Kong selling out.
This further means that the likelihood for Authorized Apple Resellers to receive enough quantities to sell through their stores within next week is slim.