I’ve had this happen pretty consistently to me now. If an NPC challenges me, telling me to drop my weapon and get out of here, I can calm them down enough to let me leave. However, if I talk to them in that window of time before they go hostile, there is no option to stop talking, other than to threaten to kill them.
No save file included because this has been happening pretty consistently.
(If the SDL is not stable, then it was downloaded at the same time as the stable build went live. Also my apologies if this has been reported elsewhere.)