Default [Q] iPhone and Unlimited Data Plan

Greetings:

Currently I have an iPhone 5 with ATT and a unlimited data plan and recently bought a Galaxy Note III international version

when I inserted the sim on the note and went online to check my bill it displayed that I has the note III and not the iPhone. My question is there is a way to spoof ATT so they can't know that I am using the Note III with the unlimited iPhone data plan ?

I had a nexus 5 before and I was able to even tether to my laptop with the nexus with no problems at all but the Nexus never registered/displayed on the site. I dont want them to force into the 3GB regular smartphone plan


Thanks for all your help in advance