Behavior Tree: Abort Sequence on Actor Value Change

Hey guys, simple question.

How do I abort a sequence when a value changes for a decorator?
For the decorator, I am selecting “On Value Change” in the Notify Observer, but this does not seem to abort the sequence when the decorator value changes. I think this just restarts the sequence. But I want to abort the sequence, not restart it.
Any clues?

Note: I don’t want to use a bool for abort the sequence. I want to abort it based on the value change of my decorator object.

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The sequence looks like this. I want to abort the sequence when the “Target Character” actor changes:
image

When it aborts, the logic has some free place on the left/right to go, it aborts itself so it does a reboot