Provider Free Platform Cache - Cache Invalidation Question

@Gaurang Mathur @Matthew Parin In the Platform Cache Considerations document, it is stated that "Some or all cache is invalidated when you modify an Apex class in your org".

I'm wondering if this is done cross-namespace, or only within a namespace? Specifically, I'm curious if ISV Platform Cache is protected from invalidation by an Apex Class modification in subscriber org's custom namespace