Hello,
According to our licence policy the paid version does not contain this link. There was a problem with paid version recognition when you manually reinstalled the free version with the paid one in previous versions, but it is fixed now.
If you have the paid package of 2.3.0 version, you can use it to manually reinstall your JoomSEF using the Upgrade function. Otherwise, please, use the improved Import/Export function in 2.3.0 version to backup your URLs and manually uninstall JoomSEF and install it again from your paid package. After this the automatic upgrade should preserve your paid version.
I'm sorry for the inconvenience.
Best regards,
ARTIO Support Team