Can you choose native or upscale? If so it is an 8kX. If you have no options except refresh then you have an 8k+. If pitool is saying 8k+ than it is likely an 8k+.
Which did you purchase? Another way is the firmware version. I would have to check but first 3 serial numbers can also be used to check.
I bought it just as 8000x in really good price.
Pitool says that headset firmware version is 2.1.255.271 ,but it was updated automaticly after i connected it. I dont know what was before.