After originally posting here, I dove into the Erlang source code and posted on the Erlang bug tracker: Redirecting…
I’m pretty far removed from this issue at the moment, so may not have much further context to share, but I believe between this thread and the one in the bug tracker, everything I observed has been captured, in case it’s useful to anyone. Looking at the Erlang source code is likely provide a lot of clarity around where any blocking actually occurs, and echoing what has been said by a few folks in a few different places, it isn’t always what you might assume or expect in regards to durability, based on the documentation.
