There are no upgrade paths from VIor SYNCHRON-ized to Synchron.
VI = Libraries recorded at Silent Stage Vienna
SYNCHRON-ized = VI Libraries ported over to Synchron Player and made sound-compatible with Synchron Libraries out of the box
Synchron = Recorded at Synchron Stage Vienna
You can upgrade your Special Editions to SYNCHRON-ized Special Edition (and I can only highly recommend doing that for all the additional content you will get, as well as a Concert D Light piano). From there it is possible to upgrade to the SYNCHRON-ized libraries.
Or you upgrade to the VI libraries and from there to the SYNCHRON-ized ones, which would be a great path as well due to the 50% VI discount right now.
Ben@VSL | IT & Product Specialist