I just got awarded the third "Custodian" badge on StackOverflow. Given my current reputation (< 800) I have access to two review queues only. So where did the third badge come from?
When taking a deeper look into my badge history, I got awarded one Custodian badge for reviewing late answers and one for reviewing first posts. The third badge I got was for reviewing an edit made to one of my answers.
Is this the purpose of the Custodian badge - or should it just be awarded for reviews of changes made to other people's posts for >2k users?