Hi Meth,
OK, so you solved this problem with missing clients. Great.
For listing only 'Main' API host on the API host list, you need to edit the current Bacularis web user in:
[Main menu] => [Page: Security] => [Tab: Users] => [Button: 'Edit' on selected user row].
In the opened window you need to unassign not needed hosts in the API hosts field.
Please note that unassigning these API hosts from this user will cause that this user will no longer have access to those API hosts (until you assign it again to the user)
Second note is that if you keep the only one API host assigned to the user, then the API host combobox at the top will disappear because for only one API host assigned this combobox is not listed and the API host is selected automatically "in the background".
If you want to hide API hosts because you need to show or share the web interface to somebody with limited access, a good way is creating a new user with limited resource access and give access to this account for that person. In the Security page you can even set read-only access per every Bacula resource or set no access for selected resources as well.
Second topic - update to 4.4.0. I remember that you use the Bacularis binary packages. The binary packages for minor releases like this 4.4.0 are available in the subscription repositories. More details you can find here:
https://bacularis.com/services/packages In free repositories are the major release packages (like 4.0.0).
To update to 4.4.0 without subscription repositories, you can also choose other installation methods (PHP Composer, Docker container images or manual installation).