It looks like it had to do with me changing my models from processing server-side to processing client side. Why would that happen? I am using caching, so I should be processing client side shouldn’t I? What might cause an error like this from client side processing my models?

Hey Mark, I came across this post today because I encountered the same error message. Seems it also occurs when you have a condition referencing a model which doesn’t exist on the page (see this post for more details.)

I think conditions referencing a nonexistent model is probably the most likely cause of this error, but perhaps it’s possible that it may also have something to do with the order your models were loaded or something.  Were you able to get to the bottom of this?