So you switched on iOS6's Do Not Disturb feature on New Year's Eve and it didn't turn itself off when you told it to? Get used to it: Apple says that automatic deactivation of Do Not Disturb is going to be broken until 7 January.
People started noticing that Do Not Disturb wasn't turning itself off as early as New Year's Day, and now two days later, Apple is here to tell you it's going to be broken for a few more days.
Apple has always had trouble with dates in the Clock app. On New Year's Day 2011, Apple's iOS Clock decided not to activate alarms for a few days. On the most recent Daylight Savings changeover, Apple deleted 3pm from the alarms reel entirely. Oh dear.
You'll still be able to turn Do Not Disturb off and on manually, but automated functionality won't be working until January 7. In the meantime, enjoy this ad for Do Not Disturb (just released...awkward) featuring Venus and Serena Williams playing table tennis. [Apple]