Ah ok, fantastic. Glad I asked then. 
Is there a recommended way to modify core models from within my plugin?
I would like to add some custom defs and relationships, e.g. a hasmanythrough with my new tables, and I’m not really sure how to best do that, other than calling functions on my new model where I have to pass in the IDs of the category and user, etc.
I found this post but it looks like he never got an answer.