No clues mate, but I noticed that too. Fortunately a lot of stores still have supplies. They dont seem to have Lavers either and havent had Nastase's for ages.
Maybe they are working on another re-issue. The last batch had a cloth interior around the ankle part, it never seemed right.
I was going to get a pair but will probably get Diadora Borg Elite instead now.
"Tennis is just chess with balls....zugzwang"
Dunlop, Prince....who knows...who cares.