Good question, Bob. The 4000 series have pretty well retired instantly: Eldred Rock, Old St. Augustine, the lenses, and the Panama set.

Eldred Rock and the Panama set are still available at retail, but Old St. Augustine and the first fresnel lens seem to be gone.

I predict that Sand Key, Florida will instantly retire also, but the Colossus and Pharos pieces will take about 6-8 months to retire.