CS told me that it is not against TOS to proofread thesis and dissertations but not any other academic work.
There are many gigs for proofing Medical Essays for entrance to med school; I was approached to proof some. However, when I checked with CS, they told me I could lose my account if I did the job. I told the client it was against TOS, and they said okay, and I thought that was that.
Then in about an hour, I got a message from the buyer saying he was upset that I had reported him to CS, and he had done nothing wrong. Then he blocked me before I could explain I had not informed him but merely asked if the service was against TOS.