I'm an admin and checkuser on enwiki. I got an email from somebody who got caught by an IP range hardblock I placed a while ago. They sent me a following screenshot of the error message:
I've blacked out the three fields which contain identifying data. The problem is that they've got garbled bits of the log message inserted in the wrong places. The first one ("account") contains the timestamp of when I placed the range block. The second one ("reason") contains an IP address, presumably the IP they were using. And the third ("expire on") contains the CIDR range I blocked.
I've got the original screenshot saved. If need be, I can upload it to checkuser.wikimedia.org.