How often does signage update if pointed to a URL or cloud file?

I now have same question. I am pointing to a Google Slide, that is shared vis Publish to Web url (so displays cleanly, without menus etc.).

When I change a slide or delete or add slides, the zoom display is not updating. (I gave it 10 minutes before cancelling experiment.)

My main need is to show a bit of info that another staff member updates a few times a week, without giving them Zoom admin access, or even partial access just to edit content; don’t want them to have to learn about any part of the Digital Signage system.)