What's going on here?
They seem to be happening in groups of four; sock puppetry possibly? This started immediately after giving some constructive feedback on a question that had received many downvotes (which was later deleted). The asker started name-calling and the downvotes started appearing on my highest-voted questions. Two days later, the downvotes appeared on my lowest-voted questions. I expected the downvotes to be reversed, but they haven't yet. This seems to be a clear-cut case of serial downvoting, even if the person doing it is using multiple accounts. Can someone look into this please?