I was told that by Squarespace that I would have to change my plan to add more users so that I would be the Administrator and they would be Contributors. Then I could manage what pages and information they had access to on my website, including Acuity. As a work around, I created a single email using gmail that was used by all of my contractors to access their calendars. That way I maintain content privacy and all of the contractors can still see/edit their calendars. Maybe that would work for others too?