Rogue Footer

I’m updating a site that has been using a now-unsupported theme, and 2016 seems to have what I need for that. My current problem is that 6 years ago when I developed the original site, I somehow inserted a footer (? 2020 – Ninth District PTA) that doesn’t seem to be in any widget area. Existence survived installation of a new theme, which I think means I did not modify any of the old theme’s files.

I can find the HTML on the site, but I can’t figure out how to change it. I’d really like to delete this from where ever it is and implement this is a more standard way.

Can someone tell me how I make this go away? Thanks!

The page I need help with: [log in to see the link]