Thanks the info. Unfortunately I upgraded to 0.3.1.7 before reading this (it didn't help), and can't figure out how to obtain 0.2.9.12 from the repos. I've tried these repos:
deb http://deb.torproject.org/torproject.org trusty main deb http://deb.torproject.org/torproject.org jessie main deb http://deb.torproject.org/torproject.org stretch main
You get tor LTS (0.2.9.x) from the official Debian (non torproject.org) repos:
https://packages.debian.org/stretch/tor