Nope, not that I am aware of, when i did the swap there was no sim card switching.. they did it all from their "retail POS" iphone. Was in and out in about 10 mins - didn't even open the retail box till I got home, the replacement phone was already setup to my ATT account when I powered it on.
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All my phones where from the same factory I know that part, I didn't save the link to look it up and too tired to find the site again, - but it was foxcon in china.
They all are Foxconn china, this is the website, but really it's the first 3 letters in the serial that matter
http://www.chipmunk.nl/klantenservice/applemodel.html/