Q: Can a PVS environment be configured with PVS target version higher than the PVS server version?

A: No, The PVS target version should be the same as the PVS server version
Configuring PVS environment with PVS target version higher than the PVS server version may work however if there is an issue that need to be troubleshot by support then it will be considered unsupported configuration

It is recommend to upgrade the PVS server first and then upgrade the targets. This is the way engineering tests the product for upgrading, Engineering does not test newer targets with older PVS servers