O2 customers eager to get their hands on nano SIMs are wondering if the company has gone back on it’s promise that, starting today, it would have supplies of nano SIMs in store for existing customers hoping to prepare for the iPhone 5.

O2 had announced on its website that O2 customers would be able to pick up a nano SIM from their store on Monday afternoon (17 September).

The O2 forum on the topic recounts the experiences of many customers, some of whom have been lucky and managed to get their hands on the new SIM, while others are still waiting to get their hands on a nano SIM.

For example, stores in Clapham Junction, Tooting and Croydon all claim to have no stock till Friday, while customers in the Birmingham, Westfield Strafford and Leeds have been luckier.

Have you been able to get your hands on a nano SIM for your iPhone 5? Which store did you go to?

We have asked O2 for furtuer information on availability of the new SIM. They told us: "They’re now in stock, however customers who are planning to buy their iPhone 5 from us do not need to pick one up as one will be included in their pack." 

It would appear that some stores simply have more in stock than others, perhaps in some parts of the country there is more competition. 

The nano SIM is smaller than the micro-SIM used by the iPhone 4, 4S and iPad, so if you have one of these devices you won’t be able to simply swap SIM cards. This new nano-SIM card measures just 12.3 x 8.8mm, and its thickness has also been reduced fractionally, from 0.76mm of the 1FF, 2FF and 3FF cards, to 0.67mm. The difference in thickness, even just 0.09mm, may cause problems when a cut-down micro-SIM is inserted into an aperture designed for a nano-SIM.

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