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I've just decided to switch our Friday schedule to Monday, which means that the test we take each Friday on what we learned during the week will now take place on Monday before we've learned it. But since today is Tuesday, it doesn't matter in the slightest.
— Mr. Turkentine

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The revised timetable puts assessment before the learning it is supposed to measure. After laying out that absurd reversal, the speaker dismisses the problem because of the current day. The joke comes from administrative confidence carrying on even after the explanation has made nonsense of itself.
Context reviewed