Seems like IT trickery people – apologies … i will seek higher authority …. maybe this one will work …
13 Aug 2020 09:45 : Update: I think I’ve got a workaround. Comments should now all be displaying, old and new.
12 Aug 2020 12:00 : Update: A ticket has been logged with the maintainer of this site’s WordPress Theme. It looks like an incompatibility with the Theme and the latest version of WordPress. All comments are still in the system, but only new comments are showing. I’ll have to wait for a response. Hopefully normal service will be resumed as soon as possible!