I have tested this numerous times and it's worked every time, can someone else verify?

I had my iphone 4 (4.3.3)JB with tetherme installed, I made a backup of it, then installed IOS 5, by default it doesnt have the personal hot spot enabled, however I then choose to restore the iphone from a backup (not to install IOS just to set up the phone etc) and voila I still have my tethering, I am sure this will last until att does a carrier change right?