Why is a Proof Clad Ike now required in the business strike LowBall Ike Registry?
I noticed this morning my set is no longer 100% (along with all other sets within this Registry). I checked, and I now see a 1974-S Clad Proof Ike is required as part of this set.
No other clad proof (or silver proof, for that matter) is required. Why this addition?