I have a spreadsheet that originally was created from a KDP download (Generate Report on the sales stats page). The first column is Date formatted as "general". The contents look like "2020-12-06".
I use the same spreadsheet to track Bookapy sales as well. So I copy a row generated by KDP for that novel and modify certain fields. One field I modify is the date. When I do that, it messes up the contents of the field. I get around it by putting a ' before the number, but the original field doesn't have that.
When I copy the field, say "2020-12-06", it looks fine. However, when I change the "6" to an "8" it changes the formatting from "general" to "date" and the result is "12/8/20". When I change the format back to "general" the field gets changed to "44173".
As I said, the way I get around it is to add a ' before the 2020-12-08 and keep it as "general".
But why is it happening? Why would Excel change the formatting for the field from "general" to "date" when I modify the contents? If it's recognizing it as a date, why did it allow KDP to have a date in a "general" field without the ' ?