here you go. with february security patches.
marlin rom zip:
https://sourceforge.net/projects/razorloves-lineage/files/marlin/
sailfish rom zip:
https://sourceforge.net/projects/razorloves-lineage/files/sailfish/
I added a kernel patch so that safetynet passes. No need for any other safetynet hacks or magisk or anything else.
I suggest you have adb logcat setup and working with your device and pc, just in case something goes wrong during the update. And have adb root enabled in developer option.
Note: The following steps are written assuming you're using lineage recovery. The same can be done with twrp, but the wording might be a little different.
*Instructions*
To update from official 17.1 to my unofficial 17.1:
1. Go into recovery and install/sideload the rom zip.
-Note: when you do this you will see a prompt on the screen about the signature not matching. This is expected since my rom is not signed with same key as official. Select yes to continue.
2. After a couple minutes the install/sideload will finish. If you don't have gapps or magisk installed, you're done so tap "Reboot system now". Otherwise, continue to next step.
3. Tap "Advanced" then tap "Reboot to recovery".
4. Install/sideload the gapps zip and/or magisk zip. Then you're done so tap "Reboot system now".