I had tested UnityVSA (community version) 4.0.1 vVOL (file/block) with vSphere 6.0 update 2.

It is ok.

When I try with vSphere 6.5, both vVOL file/block is not working.

vVOL can be provisioned but, the datastore state is inactive for vVOL block.

For vVOL file, it is not usable for the ESXi.

I use the same procedure to create the vVOL settings with vSphere 6.0/6.5.

The time settings are in sync.