Apologies everyone. Donncha pushed out 1.4.4 to resolve this earlier today which will resolve the fatal issues.
If you can't access your wp-admin dashboard in the usual way, download 1.4.4 from https://downloads.wordpress.org/plugin/wp-super-cache.1.4.4.zip, extract it and upload it, fully replacing the files in wp-content/plugins/wp-super-cache.
Cheers!