While testing out the preorder process I got to a point where this option came up...'Replace this iPhone or Buy new on existing line'..? I currently have a 6, that was not on 'Next' plan and paid subsidy 2yr contract for. I plan on upgrading using the 'Next' plan (seems to be only option) however I am unclear on which option to choose. At this point I'm leaning towards 'Replace this IPhone' just confusing. Any thoughts? --- Post Merged, Sep 8, 2016 --- Just wanted to mention, my main concern is I don't want to trade/turn in my current device. Simply want to upgrade.