Brad Feld wrote a post today about cross-posting to Medium.
He says: "...when I publish something on WordPress, update it, and then publish it again, it doesn’t update on Medium."
I've been theorizing why Medium doesn't flow-through updates from external CMSes.
I think it may have to do with the highlighting feature.
Suppose one of my posts appears on Medium.
The highlighting feature in Medium is a good thing.
I expect this is something they're working on.