Thanks for that info.. will have a look at the older versions once we get the site working again! Thankfully I did do a backup of all the pages I've edited.
Unfortunately I didn't know that we couldn't run PHP8 myself until after I'd tried to update. This evening's task is a re-install of the previous version after which I can delve into github and find the previous version of your very useful widgets etc. Every day's a school day as they say!