Xfinity xFi Advanced Security blocking a website

My xfinity network was recently upgraded with the "Advanced Security " feature.  Since then, I have been unable to access a website that I trust and have been using for over 10 years.  I am blocked on Safari for my Mac, Iphone and Ipad.

How do I override xFi's Advanced Secutiry feature for this website to allow it?

The website is www.baseballprospectus.com

Thanks,

Steve