Comment 15 for bug 1528921

As @spzm seems to have a reproduction in a very specific case and was asking for next steps, I suggest engagement of rsync upstream:

https://pserver.samba.org/rsync/lists.html

The level of deep rsync expertise necessary to turn this problem into something actionable is likely watching over there. If a thread is started, updating this bug with a link to the thread would be helpful.