Well, I don't think it really matters. I don't know for sure, but it seems like a significant portion of the Alembic business is in custom instruments. I would be surprised if even half of current production was in stock basses to go sit in store windows. With the average dealer stocking only a handful of basses, how many models can you really keep in regular production?
There is really no model that is truely discontinued since they will build any of them to your requirements. There may be some electronics package from 20 years ago that they wouldn't replicate, but you can order just about anything.
In terms of taste, I prefer the short scale SC basses and the longer scales in the Balance K shape. The fact that we differ in our opinions is why they will still build you whatever you want.
-bob