Does this mean that I can keep the iPhone but finally get rid of the chronic dropped AT&T-network calls?

The Wall Street Journal reports that:

“The largest U.S. wireless carrier will make the long-awaited announcement at an event Tuesday in New York City, a person familiar with the matter said Friday.”

I’m informed by one of the Apple Store genius dudes that it will not be possible to switch carriers on an existing iPhone because the Verizon and AT&T networks are incompatible. But I’m about due for a new one anyway.