In other words, if you sold or bought an item via the Auction House before March 18 but still haven't picked it up or collected your payment, this is your last chance to do so. On June 24, any gold or items left will be sacrificed and banished to the ether.
The removal of the Auction House has been a long time coming; it was a controversial addition to the game when it released in 2012, and the game's director admitted that its implementation "really hurt" the overall design of Diablo 3.
[Image: Blizzard]