Someone probably pm the guy / seller and told him what he had
It was very difficult to get in touch with the seller, because GB does not allow you to message someone when a listing has ended. But through some detective work, I was able to find them on facebook.
However, even though this IS a first year 88 Sporter, it's not the one I'm looking for. There was a production split where they changed from the original military stock to the thumbhole in 88. I checked the database, and I show a thumbhole 88 a few hundred units before this gun. So this would have been a thumbhole stock gun.
Still ultra rare, but it's also the same thing as the 89, which I have. I want to find an 88 that originally came with the military stock. Or, a KS-30, which was the same thing. Both super rare.