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It's in the Yoast settings Thomas.  Titles & Meta's >> Taxonomies

I'm astounded I had never thought of this as the solution to my own issue.  Thanks to everyone above.

Yes, thank you.
So no need for me to create seats then until the functionality to restrict a seat to a campaign is created then.

Do I understand correctly that in the future, we'll be able to assign a seat to a client who can then only see their specific campaign, but currently that is not available?

I just created my account and was just about to tell clients that they could see their campaigns, but decided to read about it first.