I also want to post this for everyone's reference as it seems to be the best thing out right now and it legitimately works.
Basically, you generate a iPad IMEI and then activate any new ATT sim card on the sign up/activation page ATT supplies for you(found in the link) and you can put the sim card in any device without having to worry about TTL, VPN or other means to hide your hotspot/tethering usage.
This is the EXACT same thing that those eBay sellers are offering and charging for. You can do it for free at your own expense of just a sim card and the monthly 34.99 purely unlimited data plan. And since it's prepaid, if you don't like it, you can cancel it with no worries. If you like it, you can start it again with no issues.
Here are the plans and the place you activate at ATT official site and the fine print: https://buyasession.att.com/sbd/Comm...tePlans.action
Here is the sub Reddit related to it and how to make it work along with user input of everyone else doing it and easy to follow guides (I got the links from there):