When Holly confronts Michael about Todd Packer being an unfunny jerk you can see that Erin's computer at the reception desk and Andy's computer in the background are both the older models. Right before this Erin had given Andy the new computer and Pam told him give it back so at this point Erin or Andy should have the new computer at their desk.
When Dwight and Jim are discussing possible pranks to play on Packer, Jim suggests to call up Froggy 101 about winning Justin Bieber tickets. But Froggy 101 is Scranton's Country music station therefore wouldn't give away Justin Bieber tickets.