I used to do Workforce Management for call centers, and a vacation freeze is not a sign of a big product release.
Verizon could be shutting down some call centers (outsourced or internal), or they could feel their 4G products at CES will be a big hit. You could work at a call center that they want to send more call volume to for whatever reason, usually because labor is cheaper where you are at vs another location. Verizon could be planning for a rough winter that will shut down sites, and your site is in a milder climate zone (we used to ramp up areas in the winter where they didn't see blizzards and ramp up areas in the summer that were outside of zones effected by hurricanes).
The thing about call centers is it's easier to over staff and send people home, than it is to under staff and get people to show up to meet service level goals. In a call center there are always lots of people lining up to be early released on slow days, but on an unexpected busy day nobody really wanted to come in even if we paid them extra. I guess that's what call centers get for mainly hiring college students.