Recently Lineage OS got updated with exciting new features including the Latest September Security Patch with BlueBorne Fix, New Updater app, burn-in protection for the status bar and navigation bar and other tons of fixes.
If your device is not in the above list, you can try finding it here- Lineage OS
While this is already an exciting list of devices that already got Lineage OS nightlies, the developers are planning to bring it to more smartphones.
Lineage also announced that the Lineage OS 15 based on Android 8.0 Ore is in the works: "While the cm-14.1 branch development hasn’t stopped, we’re also working on the next LineageOS version (15.0), based on the latest Android 8.0. We will refrain from giving any ETA, just patiently wait until the new branch is ready for release-time."