If you’re one of those people who’s constantly glued to your phone, you probably don’t perform iOS updates during the day— that’s peak Instagram time (or whatever your preferred time-waster is). You probably wait until you’re about to close your eyes for seven hours before you hit the “update” button. Unfortunately, this strategy could do you more harm than good.
People who hit “yes” when their iPhone asked if it should perform an overnight update to the latest iOS 9.1—which adds 150 new emojis and a new photo feature—discovered that while the phone successfully updated overnight, it also deactivated their alarms.
Which caused some people to miss important meetings.
Like a court date.
It did however, create a new alarm for one person—a phone call from the boss!
This has happened before. In 2010, a Daylight Saving Time issue tripped up the iPhone alarm system, the Verge noted.
If you don’t want to hurt your career, and absolutely need to update your iPhone, do it manually from the “setting” menu instead of simply hitting yes when the pop-up asks if you want to automatically update. Or use an actual alarm clock. They still exist.