I think that we can be more generous to a vendor who didn't test sufficiently for a failure mode that would be a legitimate use only to a (reverse) time traveller who wouldn't be able to connect the device to any network in existence in 1970 anyway. Seriously, people are complaining about problems when they go out of their way to set the date to a bogus value? Some behavior is its own punishment, people!
You mean a failure mode that is simply the time server saying "start of epoch, no offset"? There's a ton of ways for an offset to be zeroed by accident.
Hell, two years ago I was setting up logstash, and was wondering why none of my front-end searches were getting loglines. Turns out the front-end was expecting four-digit years and I was saving two-digit years - by widening my search to include the year 14AD (rather than 2014), there were my loglines.
I don't expect a vendor to intelligently handle this error and fix it for me, but I do expect a product not to irrevocably break itself if such an error does crop up.
Why allow you to set your own date anyway? The device should just talk to an NTP server. Wouldn't want a malicious human setting an incorrect date now, would we? That's dangerous!
What does "right month" and "right year" mean? Server time or local time? Either you're trusting the user's device, or your clock is always 12 hours off for some users.
