48 hours, not including shabbos. After that you move on, and you do not need to even tell the shadchan. Assuming a girl asked a shadchan to redt a shidduch to a boy, the boy is under no obligation to get back at all. Usually, the boy is not even told that the girl was behind it. A shidduch begins when the boy says yes. Yes. Whatever. That is ridiculous.
Yes, absolutely ridiculous.