Monkeytilt should update the link in the signature since it redirects people to 404 page. I don't think it won't take too much time. I also think it's because of launching the new platform like what we can read on the quote below.
Yes, I agree. Clicking on the link will lead to this message. The link needs to be updated to match with their new platform that was launched recent days.
Whoops! Looks like our monkey business took a wrong turn
Don't worry, we'll swing back on track!