O2's offer to pre-order the iPhone 3G appeared to spark more demand than bargained for when the site crashed and the 16GB model was then shown as 'not available'.
A quick chat with O2 has confirmed that the unavailability of the device is due to it being sold out, thanks to the high demand.
"We made a limited allocation of iPhone 3G stock available for pre-order online, primarily for those customers who pre-registered their interest," said a spokesperson for O2.
"Demand has been very high and we have now sold out of this allocation for the 16GB version, although we still have some available through our upgrade store."
The website is still experiencing a number of technical issues, as many clamour for the latest iteration of Apple's mobile.
"We've had a phenomenal response this morning to the pre-orders," says a spokesperson for O2. "Unfortunately it meant the site went down temporarily and we're working to restore it."
The Carphone Warehouse has been there to take up the slack though; it only went online at 11AM so should still have some left in stock if you'd rather take your chances there.