Format Date Picker for England: dd/mm/yyyy

Hello,
How can I format the date picker to insert the selected date in the English format: dd/mm/yyyy ? I’ve set placeholder text but the DATE field overrides it to be mm/dd/yyyy no matter what I’ve tried.

All we want is for the User to see the placeholder as dd/mm/yyyy and the date they choose to be entered in that way. I was previously using a 3rd party date picker plugin but have removed that at the CF7 author’s recommendation.

Have tried:
[date date-646 date-format:dd/mm/yy placeholder “dd/mm/yyyy”]format:dd/mm/yy

I’ve looked through everything here:

I see that listed as PHP supported date formats:

Thank you for your time and help!!