As a counterpoint, was the Y2K problem something that would have happened on January 1, 2001, or January 1, 2000? Sometimes the common understanding of a centu

As a counterpoint, was the Y2K problem something that would have happened on January 1, 2001, or January 1, 2000? Sometimes the common understanding of a century as being the years xx00 through xx99 is more relevant than the "technical" understanding.