Do Not Disturb scheduling feature will resume normal functionality after January 7, 2013. Before this date, you should manually turn the Do Not Disturb feature on or off.
To turn off the scheduling feature, tap Settings > Notifications > Do Not Disturb and switch Scheduled to Off.
Bullshit. Why should we have to wait a week for a bug that’s been around for years to fix itself?
Yet again, iOS is having trouble with something as mundane as keeping time.