LineageOS is the most popular custom ROM, not only because it provides standard features for phones and tablets, but also because many devices are supported long after the manufacturer ended support. The project has been offering builds based on Android 9 Pie since early 2019, and now that many devices have been updated to LineageOS 17.1 (and Android 11 support coming soon), Pie support is ending.
A new code commit to the LineageOS build server shows that no builds will be generated for LineageOS 16.0 devices anymore, which means devices that are not upgradeable to 17.1 (Android 10) will no longer receive any updates, including security fixes. A complete list of affected phones and tablets is below.
It’s a shame that so many phones and tablets are left behind, but some of them may return if maintainers can port new versions of LineageOS (or if new maintainers are found). Unofficial builds or other custom firmwares are also available for some vulnerable devices.