When did Coinbase list Arkham?

Could you elaborate on the specifics surrounding the listing of Arkham on Coinbase? I'm curious to know precisely when this occurred. Did Coinbase announce the listing beforehand, or was it a sudden addition? Was there any significant market reaction to the listing? Did Arkham's price see any significant movement following the addition to Coinbase's platform? Also, is Arkham currently available for trading on Coinbase in all supported regions, or is there any regional restriction? Understanding the timeline and context of this listing would be greatly appreciated.