This post has made me realize that I need a new category of dates in the database.

I currently have regular dates, canceled dates and disputed dates. Perhaps I should add a category for 'disproved' dates for this type of situation.

That way we can represent dates that have shown up on lists, but have been proven to not have happened.

Of course, what would be the difference between a canceled date and a disproved date? Perhaps a date like this was scheduled and then canceled.

I need to think about this for a while.