But mostly in that, the 2 collections (which is was previously and your current gist suggests moving back to) isn't as logical of a solution than simply fixing the join functionality to allow 1-n reference per field. Obviously that is possible in SQL to do and is a fairly common practice for join type scenarios like this, which is why I could see the logic in the recommendation of a single collection - as otherwise you have unnecessary duplicated data. But simply allowing references to not override each other in the current behvaiour would increase functionality for scenarios like this and save us the 5th re-write, which would be amazing - especially given all the code for TS isn't usable for us as the source DB describes the sync to TS