The 2012 Chester Arthur Dollar design was officially released on April 05, 2012. This is when the U.S. Mint officially began selling circulation strike coins to the public in rolls and boxes. The Proof coins however were issued at different times since the Mint offered different proof set products at different times throughout the year.
Most Proof Chester Arthur Dollars came in great quality ranging from PR68-PR69 Deep Cameo condition. Much fewer coins came in perfect PR70 Deep Cameo condition but the coins are available with minimal searching.