I think Will is correct in that Verizon is using some sort of DPI to detect tethering. Back when I was using Verizon’s Visible service I had to combine a VPN with the TTL mod to bypass the tethering throttle. I also use US Mobile but with a X3000. I am currently using Dark Star and as the OP experienced, it is not registering hotspot data even without the VPN. I don’t have any plans to switch over to Warp in the near future but when I do I’ll report back with my findings.