AT&T Unlimited LTE Hotspot $20 without AT&T phones

I ordered mine on the att website, free device/$45 activation, but the only plan available was 3gb/$30. I ordered it and called the connected car dept a few days later and they switched me to the unlimited/$20. It works great in the car, and is getting 14mbps down/3.5 up in my living room window, 24mbps down/9.5 up in my 3rd floor window using a USB power cord from eBay