By adding a new configuration and mapping the old CharCollection to that, we can get around having to return null the first time, by obsoleting the old one and redirecting to the new GetCharReplacements method
Since this is the way it's been previously, we cannot change the behaviour of this. Unfortunately due to how the config binding works, we have to make sure it returns null the very first time it's called by the framework to ensure that overrides actually gets registered.
