How would an Heir of Time's body change? and maybe the other Heirs too while you're at it

Time is too abstract of a concept, I feel there could be a lot of ways things could go, maybe just happening to always be a Doomed Version and a new Alpha popping from somewhere else? And as I’ve said in the past, I’m not even sure every Heir has to have an analogue to the wind poofing John has. I already kind of talked in the past about Heirs changing themselves though didn’t I?