I would disagree. Its been many days now that my initial 2gb got exhausted and i am on the unlimited preview offer. All the while i am using it on an iPhone 6S. The only time i used it on Samsung which was an s6 and only on the first day to activate the preview offer.
I think the preview offer continues to work as long you use the sim on a VoLTE device after activating it for the first time. Once if you switch to a non volte 4G device it gets deactivated.
