Ember-Data filter on async relationships

I have a scenario described on StackOverflow where I am doing a this.store.filter and in my filter function I am trying to deal with an async relationship.

I understand that the filter function is passed a resolved model but I would also like to do some logic around its relationships. This fails now and does not seem to do any live updating if I take additional steps to resolve the properties prior to the filter, run the filter, then update the related properties after. This behavior seems to be contrary to the documentation

If any of a record’s properties change, or if it changes state, the filter function will be invoked again to determine whether it should still be in the array.

My assumption is that this doesn’t apply to the relationship because it doesn’t really change, its just a sub-property is the part that is changing. Is there an idiomatic way to deal with this scenario, in my route, or am I best left to dealing with a computed property in my controller/component