Hi Tom,
After much investigation, I narrowed down the cause of the latest version of Elementor not loading pages to the Code Snippet used to implement the Remove Query Strings as provided in the Optimize GeneratePress page.
Once I deactivated the snippet, all pages were able to be loaded as usual. It should be noted that this was working fine on Elementor 1.8.12.
Obviously not a GP/ GP Docs issue but I thought that I should mention it here if anyone else is experiencing this behavior with the latest update to Elementor.
Cheers!
Lyle