I have some in the 'CD' annodized flavour. I have also asked the same queston on here. They are def from the 231/261 era with the yellow labels. The profile looks like the later 217s but they are not welded like the later 'SUP' rims.
Anyway i didn't get an answer so I am thinking....a) They are low volume release of what became the 217...or b) they are a variant that was sold just to OEM bike producers.
They are actually really good rims.
Ant