So given that the S200 is definitely made by CZ.
and the Tau 200 is made by Tau BRNO (a different company to CZ).
It's looking like the the original S200 was a new design based on a conversion done by others to a Tau 200 rather than a conversion of a companies existing product (unless Tau was a subsiduary of CZ at any time)
Whether this was commissioned by Air Arms or CZ is another question.
There appears no lineage from any pistol thus far...
Perhaps someone here knows someone at AA who might know?