Where to set property values on newly added components

I made a new component, and set the default value of an integer uproperty to -1.
What i want to do, is, when, in BP editor components tab, i add this component to the BP, the integer uproperty is set to Max of the same property across all the components of that type in the actor.
I ONLY want this to happen in the editor, when the new component is added.
I’ve tried OnComponentCreated, OnRegister, PostLoad, etc, but whereever i set the uproperty value, in the details panel it always shows up as -1. It’s not a logic error, because even if it doesnt find an owning actor or any other components, it should still set it to 0.

tl;dr which method do i use to initialize default properties from a component ONLY in the editor AFTER it’s been added to the actor ?

I think i know what I’m doing wrong, but see no solution to it:
The details panel shows the properties of the template component object inside the UBlueprint itself, and that thing has no lifetime methods called on it like PostLoad or OnComponentCreated or OnRegister, so since my code was in those methods, it was setting the properties on the PREVIEW SPAWNED ACTOR’S RUNTIME COMPONENTS, which is not what the details panel is showing to me (instead, when the details panel is edited, the preview spawned actor’s components are recreated).

How do i accomplish what i wanted ON the actual template component in the UBlueprint ?

Any progress on this issue?