On the drop-in filters, wouldn't they keep making (at least, selling them) for a while even if future lenses wont use it? There's going to be a lot of lenses in the field that might need spares/replacements. Having said that, the alternative isn't any better - that the supply chain is badly planned.
Definitely. This is just a sign of bad supply chain management. I would hesitate to read it as anything other than that.