Retaining unlimited data is a BIG deal! And we don't want you to lose it if you need it. So, let's go over your options. First, may I ask how many GB's your line has that you want to keep your data package on? Even if you're a heavy user, you may wish to check out this program to retain the feature http://vz.to/ZILXBT . Next, in regards to your question, only the line you upgrade has it's features updated so you can transfer the phone but you'll want to make sure of your features and even contact customer service at *611 shortly after upgrading to make sure everything is as you want it.
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