Description for the expiry date/duration field suggests and incorrect date format

Currently the description for the role expiry date field suggests that the user input their date in the format "dd-mm-yyyy hh:mm:ss" - this is then being passed straight into the PHP strtotime function which unfortunately doesn't handle UK date formats correctly.

I would suggest the quickest solution to this is just to change the suggested date format to something more like UTC, i.e. yyyy-mm-dd that way we remove the confusion around UK and US date formats.