Following reports about the existence of a flaw bricking its iDevices, in a support document Apple has now officially acknowledged that the “January 1, 1970” bug affecting 64-bit iPhones, iPad, and iPod touch devices exists.
The document (which shows today, February 15, as the date of modification), doesn’t offer a fix, but simply mentions that Apple will issue a software update to fix the issue.
If you changed the date to May 1970 or earlier and can’t restart your iPhone, iPad, or iPod touch
Manually changing the date to May 1970 or earlier can prevent your iOS device from turning on after a restart.
An upcoming software update will prevent this issue from affecting iOS devices. If you have this issue, contact Apple Support.
You may recall from earlier reports that manually changing your iPhone’s date to January 1, 1970 will render your device useless, as it triggers a continuous reboot cycle. Some users have, however, reported successful restores through iTunes in DFU mode.
The support document doesn’t detail the reason behind the mysterious bug, though Tom Scott, a YouTube video maker and programmer, speculates that by changing the time to a date to January 1, 1970 (which is Unix Epoch time 0), the device gets bricked because of an integer underflow (via MacRumors).