I used the query in this answer to see the number of edits per month and I was fairly surprised as April 2017 had $86,444$ edits.
The graph of edits per day is even more surprising as one day had $55, 073$ edits, though I am unable to pinpoint the exact date! I am vey surprised because referring back to the graph per month, the second most edits in a month was $33, 740$ edits on November 2015.
Is this a random event or a processing error? Or did something occur so that so many edits took place (retagging, etc)? Or is this a problem in the query?