A very short summary if anyone else is (still) stuck in the same situation, doesn’t feel like going through the backup-reflash-restore backup route, and had already enabled developer mode prior to updating. If you don’t know how to do some or all of these things, I think all information is in the posts above (starting at post 124) and it’s best if you read them through first.
- open recovery mode (install it via flashboot first, depending on your device)
 - use the shell, not ssh
 - mount /home according to the instructions here
 - remove all traces of harbour-callrecorder and osm-scout-server
 - install all of the packages in /home/.pk-zypp-dist-upgrade-cache (it’s a bit of trial and error which ones you need to install first, but you can always upgrade all of the packages in a specific directory at the same time)
 - you can install all packages in a directory with this command: 
find -name \*rpm | xargs rpm -Uvh - (reinstall the normal boot mode with flashboot, depending on your device)
 - reboot the phone normally, at this point it should no longer show the white screens with “No apps running” but stay completely black
 - connect your phone to a charger - if you hear the bell, you know you’re on the right track (or if you hear an email notification or whatever native Sailfish notification that only needs Wi-Fi)
 - immediately ssh into your phone, run “ssu re 4.6.0.11” and “version --dup” (if you have it installed, temporarily disable the chum repo first, otherwise you’ll get some errors)
 - run “reboot”
 
Your phone should now reboot into a fully working 4.6.0.11 installation, only the ambience will have been reset to a default ambience.