Most any time you see a date of Dec 31 1969 where it doesn't belong, it tends to suggest a system that was moved from a Micro$oft environment to a Unix-based setup.
This forum changed hosts about 15 years back, IIRC.
The forum database did not get properly scrubbed, and old data was interpreted in interesting ways by the new host system. The data format for date and time in the old system was not compatible with the new one, and would come across as a zero.
All dates/times in a Unix environment are expressed as a ginormous binary integer. Pretty sure it's the number of "system jiffies" (1/60th of a second) since midnight, Jan 1, 1970.
If the date field contains all zeros, because of a translation error, you get a date one-sixtieth of a second earlier, Dec 31, 1969.
There were a few hiccups in the move from the old host to the current one. The number of posts for each user got hosed, and had to be manually corrected.
But that's the short version. Any post that shows that unlikely date was posted to the system before the big move.
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