Customary in USA is mm/dd/yy. Except in the military, where they put the month in the middle, but usually spell it out (e.g. 04APR01). On the continent, I was taught to do it dd.mm.yy. With periods instead of slashes.

So I foolishly figured if it has slashes it starts with the month, and if it has periods it starts with the day.

Nothing is ever so easy.

Alex