No offense intended, but this question is useless.
You should first know what your actual requirements are, and then only start to implement.
Whether the UPD comes "before" or "after" the JNR (looking from a source) is a matter of what you have to implement.
In fact I haven't seen any case yet where it really would make sense to have an UPD "before" a JNR. Usually it makes more sense to first join two data streams and then define (using an UPD) which of these combined records has to be inserted into a target, updated there, or removed.
But again, this is a matter of requirements. The fact that I haven't seen any such case yet doesn't mean there is none. It only means that I haven't seen too many difficult use cases yet.