This might all be wishful thinking, but, AT&T has just updated its corporate retail stores with a new memo, informing employees that in order to keep up to date, they need to scrap all their old micro SIM cards for a new incoming micro SIM that supports LTE. Currently, only one device on AT&T uses a micro SIM, which is Apple’s iPhone, but Nokia’s upcoming Lumia 900 will also use the new micro SIM LTE cards.
But, and this is a stretch, there is a slight possibility that there is another device that is upcoming, that will also use the micro SIM LTE card and that would be Apple’s iPad 3. With a rumored introduction on March 7th and possibly roll out by March 14th, it would beat the Lumia 900′s (March 15-18) release to the market and could then require the use of the new cards.
This could all just be one big coincidence, as AT&T might just be preparing for future phones, like the Lumia and the eventually iPhone 5/6 that is also rumored to use LTE. But with the new iPad 3 heavily rumored to pack LTE, this is still a possibility.
Source: Phone Arena