It's a Mustache templating error, fixed on master in the submodule, but apparently not in the current deploy. I moved from {{template vars with HTML escaping}} to {{{raw template vars}}} sometime back. Bad merge, perhaps. There have been quite a few changes, in response to feedback!
> must be limited to a period of 30} consecutive calendar days.
The stray “}” is clearly a typo, and if the description in the Manifesto is correct, the “3” should be a “9”.
This is kind of critical stuff to get right in a license.
[0] https://licensezero.com/licenses/noncommercial