|When the day in your date is less than the 10 how many digits does it show?|
ie for the first does it show 01 or 1
this worked for me assuming 01 for the first (After some testing, apparently 01 and 1 did not matter) place the following in B1
Oh and then you need to format your cell for the date format you want
This assumes your data is in column A and starts in row 1.