Upgrade to iphone - where??

[Hamzter]

I'm currently on a non-iphone contract with O2 that's up for renewal and I'm wanting to upgrade to an iPhone 3GS, only when I vist the upgrade store on O2, there's no 3GS to choose from, only 8GB 3G ones

Anyone know how I'm meant to upgrade?

 

[Hamzter]

Looks like I'm going to have to upgrade in store then, since they don't have them as an upgrade online, or by phone apparantly. Will head to an O2 shop tomorrow, there's a stock checker on the website but unless I'm being stupid it doesn't actually tell me anything?

http://shop.o2.co.uk/update/stockupdate.html

Clicking the 'check availability' link brings me to a store locator with no stock information