UI Configuration - Hide Specific Relationships Issue

So, I have two Objects, a Job Card and a Department Task.

Job Card is the Owner of related Department Tasks.

Each of these objects are related to a number of other object types, People (in terms of assignees, owners, checkers etc), Customer, Project and so on.

I am trying to limit how many related objects are displayed in M-Files for both Job Cards and Department Tasks. I initially created a rule for the Job Card to hide some related objects and this has worked fine.

I've now created a second rule to hide some related objects from the Department Task and this rule just will not work. However I try and configure it, it is not hiding any related objects at all.

If I edit the Job Card rule to add or remove related objects, those changes are working. 

Why can I not get two rules to work?

Any ideas? I'm stumped.

Thanks in advance.