Bug#762194: Debian has abandoned many users also on upgrades by the CTTE decision on December 4 2014
Looking at the IRC log
lines 197 to 280 reveals the plan.
Conclusion: quoting <vorlon> Steve Langasek: "we recommend/support
systemd being the default init system for upgrades as well as new
Action point: quoting <dondelelcaro> Don Armstrong:
"#action dondelelcaro to draft affirmative resolution on #762194 noting
#757298 et al"
More details: (if using apt, see also #757298 about the grub2 entry)
- upgrading from Wheezy/with sysvinit to Jessie can boot with
init=/lib/sysvinit/init unless/until the sysvinit package is removed by
CAUTION: don't autoclean until you have installed sysvinit-core if you
don't want systemd-sysv!
- dist-upgrading Wheezy/with sysvinit to Jessie will get systemd-sysv,
and sysvinit will be history!! (unless you install sysvinit-core on next
reboot (if your system boots))
- grub will obtain a menu entry to boot with init=/lib/sysvinit/init if
something goes wrong with the switch to systemd-sysv (unless you
dist-upgrade). If you are using some other bootloader, e.g. LILO you are
on your own.
- people not careful enough are on their own: quote from Tollef Fog Heen
"at some point, it's the user shooting their foot off"
I wonder what the people not having physical access, e.g. ssh, to their
boxes should do, not even able the see the boot screen?
Very nice conclusions and actions ;)