On the Products page, select Default Settings for the product you want:

Select the Coming Soon tab and you can customize the settings under Date Format.

Preview:

If you'd like to hide the date on your products page, you can select this option in the Placement of Date dropdown.

To see the list of available date formats, you can hover over to "i" button and a list will show:

Manually type the format into the text box. For example, if you wish to show a double-digit form of the day (01, 02, 31, etc), please key in [DD] into the text box:

Select Apply when ready.