Due to a number of changes, the next system upgrade will require manual intervention.
Yet again, I discovered a bug in Sisyphus. This time in it's dependency parser (thanks bsd4me for help), and as a consequence, it must be the first package to be upgraded :
sisyphus --update (resync the trees)
emerge -Gva sisyphus (pull the latest sisyphus v3.1910.1-r2)
sisyphus --rescue (will refresh sisyphus's binary database with up to date information, optional)
Once it's complete, you can do a full system upgrade :
Here comes the tricky part. This upgrade will replace sysvinit with openrc-init as PID1. Once the system upgrade is complete, you won't be able to shutdown or reboot your machine. If your machine has a reset button, use it to reboot. If not, you can still reboot the system using MAGIC_SYSRQ :
Press and hold Alt + Print Screen and then press R + E + I + S + U + B in order.
Once the system reboots, openrc-init will take over and boot the system. Now may be a good time to remove any orphan packages :
Assuming everything works, congratulations, you just performed the system upgrade.
Changes aside this system upgrade is intended to make your life much easy from now on. Here is a brief changelog :
P.S.: if you installed proprietary nvidia-drivers by other means (aka downloading from nvidia website, this upgrade will likely cause issues, please start from a fresh install).
P.P.S.: the above instructions will work and must be applied on existing installs or on fresh installs made using the 1908 Redcore release. A fresh ISO image will come out soon, incorporating all the changes.
I would like to apologise for any lack of progress in the last month and a half, but some health issues kept me away.