Blackboard conditions in different subtree

I was wondering how Unreal handle the following situation.
Imagine that the optional decorator is a blackboard decorator. As such, there’s a condition before the AI can pick up the ammo.

The AI currently has an enemy and is attacking the target. The new decorator condition’s value has changed. Since the Needs Ammo subtree is not active, will the new decorator still be notify of the change? If it does, I suppose it will also have to check if Needs Ammo is set. And if “Find A Pickup” node also had a condition, it will have to check that one too since they are in a sequence composite. In other words, when a blackboard decorator gets a notification, it has to check every condition from the node up to the root to see if its really going to get execute.

Is my understanding of the situation right?

Thanks

Every condition and parent condition related to a certain task has to be true in order for a task to run. In addition, decorators allow for tasks to be aborted if desired.