My guess is as good as yours, but it could be a moderator action. Sometimes submissions are manually upgraded/downgraded by moderators here (that would be dang)

My guess is as good as yours, but it could be a moderator action. Sometimes submissions are manually upgraded/downgraded by moderators here (that would be dang). Related: https://hn.algolia.com/?dateRange=all&page=0&prefix=false&sort=byDate&type=comment&query=%22upvotes%20alone%22%20by:dang https://hn.algolia.com/?dateRange=all&page=0&prefix=false&so...