Generally, I'd say the official unofficial policy on name changes is that from an IC perspective, they can be considered retroactive. That is, once you, the player, know that Monte Cristo was once named High Guard, your characters all know that the character was always named Monte Cristo, and everything that High Guard did, they know was actually done by Monte Cristo.
This is because name changes are not an IC tool to change your RP or escape from a bad rep; they are an OOC tool to change bad/inappropriate names into good/appropriate ones.
