I am no expert. but it seems to me that there are three formats for dates:
American 11/26/01 (example, November 26, 2001)
European 26/11/01 (exemple, le 26 Novembre, 2001) (French)
Ordinal 2001/11/26
So, if you put in 29/10/2001, it is reading it as an ordinal = 2029.10.01 which...