For whom it may concern:
Apple is aware of the problem and is working on a fix.
https://support.apple.com/en-us/HT205248 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.
When the date of a 64-bit iOS device is set to January 1, 1970, the device will fail to boot.
Connecting the device to iTunes and restoring the device to factory defaults will not put the device back in working order. Instead, a physical repair is required.
When connected to public Wi-Fi, iPhone calibrates its time settings with an NTP server. Theoretically, attackers can send malicious NTP requests to adjust every iPhone's time settings to January 1, 1970, hence brick every iPhone connected to the same network.
How to fix this issue:
Apple Support teams worked through a few steps and came to the conclusion that disconnecting the battery and reconnecting fixes the issue and allows the phone to boot to the lock screen.
It should be common knowledge to all stores worldwide
https://youtu.be/ofnq37dqGyY
