The company I work for has a plan through AT&T. We were recently eligible for an upgrade so I purchased a new iphone 4 but before activation decided to keep my 3GS. Must I activate the "4" even if I don't intend to use it? Wasn't sure how this would affect my next upgrade date.
I do believe you will need to activate it cause if you don't you would have to return it and once it's activated, the micro-sim in the iphone4 will become active and the sim in your old 3GS will no longer work. In order to keep using the 3GS, you will need a micro-sim adaptor, then you can put the micro-sim in the 3GS and continue to use it and do whatever you want to with the iphone4.
Also, your next upgrade date will be based on when you upgraded to the iphone4, i.e. 18-21 months from now.
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