I found out the issue. I completely overlooked/forgot, I had the below Caching Code in the .htaccess file. School Boy error!
Once I removed the below code, the Basket Caching Problem was resolved.
## EXPIRES CACHING ## <IfModule mod_expires.c> ExpiresActive On ExpiresByType image/jpg "access plus 1 year" ExpiresByType image/jpeg "access plus 1 year" ExpiresByType image/gif "access plus 1 year" ExpiresByType image/png "access plus 1 year" ExpiresByType text/css "access plus 1 month" ExpiresByType application/pdf "access plus 1 month" ExpiresByType text/x-javascript "access plus 1 month" ExpiresByType application/x-shockwave-flash "access plus 1 month" ExpiresByType image/x-icon "access plus 1 year" ExpiresDefault "access plus 2 days" </IfModule> ## EXPIRES CACHING ##
Should I discover a way to cache a website, without the Basket being Cached, I will add it to this answer.