No it doesnt make sense.
I guess if no-one inputs a date then it comes up as 00/00/00

Supposedly, where there is a valid date in the first column and then 00/00/00 in the second, it means the approval was cancelled or replaced or chips were redeemed. Often, it must get corrected after the fact, but you don't see it until after the year end when the new cumulative file is produced. There are many typo's though. I have not just the cumulative files saved but also every single monthly one since day zero so I can go back and see when an entry first appeared.