Fix for "1970 Date" Bug Fix
If you manually change the date to May 1970 or earlier on your iOS device, it can prevent the device from properly restarting. It's a serious problem but it's one that Apple plans to fix in a future update, probably iOS 9.3.
The company has confirmed as much on its website. Apple says that an "upcoming software update will prevent this issue from affecting iOS devices."
It doesn't say iOS 9.3 but odds are good that it will be the update that delivers a fix. The recent iOS 9.3 betas squashed the bug for good which means the public version of iOS 9.3 should as well.
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