I wasn't asked but I will provide some input on this anyway, seeing as I was one of the people that received a masters in jeopardy email.
I have
630,663 approved hits
99.87 approval rating
796 rejections.
Sorry, I meant to tag you too. Crap, 796 doesn't seem all that high really.
It seems there's some sort of stats-pull that the nerds behind the MTurk curtain periodically carry-out, which is why we see batches of people be given Master's and apparently now batches of people be threatened with revocations...
What's unclear is whether there's a specific threshold for raw number of rejections to trigger revocation or if its the approval % that counts... Like the expectation is that people with Master's stay above something 99.90% approval, which you're obviously just below.