Introducing HTML/CSS templates

Thank you. I’ve tried using the date filter as described on that page, but I can’t get it to work. I’ve tried:

{{ issue_date | date: "%-d %B %Y" }}

I’m expecting this to give me ‘1 January 2015’, but instead I’m getting ‘-1 B Y’

Am I doing something wrong?

Edit: @lubos, this question got a little buried in the thread and I’m just wondering if you have a moment to look at this. Many thanks.