After updating to 1.485 some of my builds broke. When checking the workspace they were all deleted.
I found out that workspaces on slaves are deleted after 30 days of inactivity.
But I don't have any slaves, and these workspaces are never updated, since they only contain some ANT scripts, or plain batch, that only copies files outside of Jenkins.
My last version before this update was 1.481, I am running these scripts for over a year, and nothing like this ever happened.