Actually, this was fixed right after the release (probably even before it started being reported here), it was an oversight.
The fix will be included in the next build with a bunch of other fixes/improvements.
Aw, sorry about that 
refreshing the UI only once should have helped.
Btw, any clues on how to reproduce this more consistently? It’s very weird, there’s a variable that gets unassigned in between clicking on “change job” and showing the promotion tree, so when the promotion tree is loaded, it’s as if it doesn’t have a hearthling selected and can’t show the job info related to that hearthling. No idea how the UI gets into that state, but we’ve seen it reported several times already.