Property derivation for "Plan Type" is overridden by Property Inheritance

Summary:

I've an use-case wherein the Parent Node is "true" for all the plan types whereas the children rolling up to the Parent Node may or may not have "true" for all plan types. We're deriving that based on a property value instead.

However, the derivation is being overridden by inheritance. Is inheritance > property derivation? Shouldn't property derivation also be considered as an "override" ?

Additionally, I am not able to turn off "inheritance" for just one node type. It's only letting me to turn it off at the application level. Is this how it is supposed to be?

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