I am part way through upgrading an old 6.7 system to 8.0. I tried to go direct to 8.0 but was forced to upgrade to 7.0 first. I now have a stretched vSAN cluster of two esxi hosts running 7.0.3 and a witness running 7.0.3.
I was able to upgrade my windows vcenter to 8.0.
Each of the vSphere hosts was assigned a 7.0 license no problem.
The vSAN license 7.0 will not assign "The created license with serial key XXXX cannot be assigned to the chosen asset"
My vSAN eval license expires in 3 days!