Discussion about the Korg PolySix synthesizer

Hi,

I have seen in the Polysix service notes at the Old Crow's web site 
mention of Old & New Production Polysix versions.

Has anybody got any idea as to when they switched over - i.e. what 
range of serial numbers are Old & New?

Thanks,
Andy.

http://www.synth.clara.net/synths.html