(eBay isn't here in this forum and not listening to you)
I suspect that they have changed the internal mapping of some of the IS (like the old change with the country of manufacture), and that although the visible label on the IS is the same (Composition), there is a new IS with that same visible label that is going to be suggested or required, and the old one will be deprecated, not required, or otherwise just a user specifies IS (that unfortunately has the same visible name as the old.)
Adding the new and deleting the old may be the intended path for the upcoming category and IS changes.