Jost comments on Harry Potter and the Methods of Rationality discussion thread, February 2015, chapter 110

[Jost]

Thanks! (The translation is fine, btw.)

A few lines later, McGonagall states it even more explicitly:

»Das wäre eine schöne Bescherung, wenn ausgerechnet an dem Tag, da Du-weißt-schon-wer endlich verschwindet, die Muggel alles über uns herausfinden würden.«

(rough back-translation):

“That would be a big mess, if the muggles found out all about us, right on the same day when You-Know-Who finally disappeared.”