This may be AT&T's tactic to prevent people from switching over to Verizon's iPhone and in turn win it's old customers back.
In an unadvertised loophole, AT&T has allowed subscribers who have had an unlimited data plan in the past to switch back. That includes anyone who had an iPhone before June, when the limited plans took effect.
Jose Argumedo, of Brentwood, N.Y., says he and a friend were switched to an unlimited plan recently after they called AT&T's customer service. Both have iPhone 4s, and previously had earlier iPhone models.
The company has allowed iPhone and smart-phone users with unlimited-data plans to keep them when upgrading directly to a new phone. It's the option to return to an unlimited plan after going limited that's been secret.
Another iPhone subscriber on a limited plan called AT&T to see if he could switch to the unlimited one, but was told he couldn't because he hadn't previously had the unlimited version.
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