Yes I know but I would like to override it in C++ not Blueprints. The same goes for AbilityStarted/Ended/Interupted etc I have changed it to virtual by my self and it doesn’t causing any issues for now but I don’t like to make this change with every update.
Please be aware that some of users are using C++ instead of Blueprints to have necessary references in C++. Basically with UAblAbility there aren’t any virtual C++ functions that can be override and you can imagine that OnStart/End are the most important and I needed to create this functionality by my own in AbilityInstance (just call my virtual functions before Blueprint event)