Verizon’s new upgrade conditions for the its Edge plan may be little more than a marketing trick meant to convince subscribers to stay with the carrier amid increased competition elsewhere. The carrier has dropped the upgrade time from six months to 30 days for its Edge plan, allowing users to upgrade to a new smartphone in just one month, if they so desire. The promotion is limited though, as CNET has learned. “[…] this is currently a promotion but we have not set an end date. It is in response to our customer’s requests regarding this popular payment and upgrade plan,” a spokesman told the site. “While it is important to understand what our competitors are doing, Verizon makes decisions based