How exactly are network updates calculated?

steamcore

I am a little confused about how photon calculates how many network updates you are doing. For example, I am using a couple of different assets that handle smooth sync over photon. If my update rate is 20, and I have a few of these components in the scene, does each one of them add 20 messages per second to my room total? Or are they aggregated and queued somehow?
R PCs and events are added on top of that too, correct?

So if I wanted to make sure that absolutely everything was the lowest total messages, what I should do is queue every single update with a manager and have that manager send everything all at once, correct?