Corrected entry: Harry and Dumbledore apparate from the tube (train station) at few minutes after 11 p.m. (as evidenced by the date that Harry made with the waitress for when her shift ends at 11). However, they apparate to the town where Prof. Slughorn is hiding and the grandfather clocks reads approximately 10:26 p.m.
MovieFan612
21st Dec 2009
Correction: The grandfather clock is simply wrong, and there are actually at least two reasons that can be: One, Slughorn has faked an assault by the death eaters on the house, and in the process of creating that chaos, the clock might have been harmed. Or two, and even simpler, Slughorn states the owners of the house are away on holiday, so the clock has stopped, because it wasn't wound up regularly.
Ioreth