No it won't work. To preserve unlimited the upgrade has to be from a dumb phone. You can't upgrade a smart phone and then transfer it to another line to keep unlimited.
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This is not a change. Any upgrade used by a line that has unlimited has always lost unlimited. See my above post. The upgrade has to be on a line with a dumb phone then transfer the new phone to the unlimited line.
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Tried this today at two Verizon stores, one corporate, one premium, they said no-go. If you try and use an upgrade from a line with unlimited data in any way, ie transferring it to a dumb line, the original line loses its unlimited data. It would appear they've closed the loophole, but if anyone can confirm this is still working, would love to hear it as I can't seem to find a place that will do it.
This is not a change. Any upgrade used by a line that has unlimited has always lost unlimited. See my above post. The upgrade has to be on a line with a dumb phone then transfer the new phone to the unlimited line.