Replace ViewControllers in Column?

I've got a doubleColumn UISplitViewController and I'd like to retain the automatic behavior of the Collapse/Expand Primary Column button.

To this end, I'm not specifying my own UINavigationController for the .secondary column position.
There are moments in my app's run time that I would like to replace all of the view controllers in the .secondary column.

setViewController appears to push an additional controller onto the nav stack. Is there an API available to replace the controllers with a new set?
The context of this question is setting ViewControllers into the secondary column when in a compact environment. It appears as if it always retains the first view controller no matter how many additional ones I set.
Replace ViewControllers in Column?
 
 
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