Tesla are concerned that 4G does not work in much of australia, particularly rural areas, so they are sticking with 3G. Given we don't get an internet browser even when stationary, its unlikely 4G will be a gain for us. My DS in Richmond advised me that the hardware change isnt difficult should the policy ever change.
That's a weird reason for not enabling 4G. The radio should be able to automatically fall back to 3G when 4G is not available, just like mobile phones.
I think someone mentioned in another thread that the upgrade will cost about US$500 if you don't already have the right hardware.