Is There a Black Hole That Changes?

Two black holes that have the same mass, spin and charge are totally equivalent. There's no way you could do experiments to tell them apart except for a tiny crack in the 'noher theorem' A non changing black hole is sort of rious and impenetrable but if it changes then we can learn something about its innards. The event horizon has a different shape because they haven't formed the singularity or quantum fuzball yet.