Another xFi advanced security blocking legitimate site post

I'm trying to access the community section of a site dedicated to promoting interoperability for K-12 schools, districts and related vendors. xFi's advanced security feature is blocking it and provides no reason as to why.  The site is www.projectunicorncommunity.org (parent site is https://www.projectunicorn.org/ for those who might be interested).

I know I can disable Advanced Security, however that is a bandaid and doesn't really solve the problem IMO. Comcast should either provide guideance as to why the site is blocked (so the owner can take appropriate action) or allow customers to create their own whitelists.

I'd love to have Comcast unblock the URL, that would make my day.