Each edit, even with unrelated edits. I had a README referring to something as "the cathedral of s*t" (some HN commentators don't care for the swearing, which is systemically bad news but w/e) and the robot would lift that phrase out in drive-bys, repeatedly.

Occasionally it would report the action, sometimes it would not bother to report it. It never reached into the README on an unrelated doc edit, but if it was touching the README, that line was getting excised.