I contacted UvA to notice them about a mistake they made enrolling me to the Grid Computing course (!). The following is the automatic reply.
Dear Sir, Madam,
Summer is a very busy period for the International Office. Of course we will try to answer your question as soon as possible but it might take us more time to reply your e-mail(s).
Dear UvA, summer doesn’t even exist in the Netherlands. That’s a weak excuse.