Good question, magenta6572305! Being able to trade it in while in a store would absolutely give you peace of mind that your full promo credit will be processed versus mailing it in and your fate being left to the shipping company. When you pre-order a device online it has to be mailed back. The last time I mailed back a phone, I wrapped it in a layer of bubble wrap inside a padded envelope and everything arrived in the same condition I shipped it in.
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