The post list made it look like the OP had responded again:
But he hadn’t; there was a whisper (after mine):
I kinda get why I got the behavior I did, but it was misleading.
At a minimum, the UI shouldn’t highlight someone who isn’t actually the most recent poster. Ideally(?) it would add a… greyed-out? avatar of the whisperer. And obvs that greyed-out avatar would only be visible to those who can see whispers.