Apple's UK iPhone 3G network disappointed thousands of customers yesterday with news the device is now out of stock for online pre-orders.

The website said: "Due to huge demand for iPhone 3G, we're currently out of stock online. Come back on 10 July for more information."

Official: O2 announces 3G iPhone tariffs

That's harsh news for the thousands of existing iPhone customers who pre-booked with O2 for information on how to upgrade. O2 approached all these customers yesterday morning to offer them the chance to book in a fast upgrade to the new model.

What perhaps makes the affair more annoying is that O2 has also admitted to holding no stock yet of the 16GB iPhone 3G, while also only offering the device in black.

Apple is believed to have delivered a similar volume of stock for sale in O2 and carphone Warehouse stores, as it did for online - so all customers must now queue for availability on Friday.

See our 3G iPhone spotlight on Mobile Advisor