@tyxo , the term ‘Unofficial’ is not necessarily different from ‘Official’ in the sense of code and result. You can build a custom ROM purely based on the code provided by the LineageOS Android distribution team without any additions, and the result will be exactly the same as a so-called “Nightly”, minus some ‘fingerprints’ here and there that show who built it. And: ‘Official’ is not necessarily better than ‘Unofficial’.
For many popular devices, there are both, and the developers of the unofficial versions add tweaks to differentiate themselves, e.g. a customized kernel, a stripped-down build (i.e. some pre-installed apps removed) designed to the developer’s taste. …
The official version isn’t always perfect, either. Sometimes ROM developers have unreleased patches that have not yet been released to the upstream, or they were not approved during code review for various reasons, leaving long overdue bugs in the official builds. Developers can release unofficial builds that already include these bug fixes when they are built locally, which fixes the bugs.
When a new Android version is released, so-called unofficial builds are almost always released first. This is usually due to the strict requirements that the /e/ development team wants to enforce for official versions.
Since the /e/ team lacks manpower { … @Manoj … we do have developer bandwidth issues. … } I don’t expect official /e/OS versions for the SM-G920F and SM-G925F.
I’ve already tested various custom ROMs for the Galaxy S6 SM-G920F. The current /e/OS-R V.1.15 by @ronnz98 is currently the best for me