Ahhh - yes, the old versions used the VST2 wrapper and generated both VST2 and VST3 at once.
When presented with both VST2 and VST3 versions of the same plugin, it looks like S1 will choose the VST2 version, but only has that little text in the lower right corner that identifies the species.
Thanks, Frank - that’s exactly what was going on. Good to hear from you man!
Will