Hello,
i can confirm this when upgrading from cron 3.0pl1-127 to 3.0pl1-127+deb8u1:
Setting up cron (3.0pl1-127+deb8u1) ...
update-rc.d: warning: start and stop actions are no longer supported;
falling back to defaults
I think this is triggered by the postinst script (in my case package
cron_3.0pl1-127+deb8u1_amd64.deb on line 85) using update-rc.d start:
# Automatically added by dh_installinit
if [ -x "/etc/init.d/cron" ]; then
update-rc.d cron start 89 2 3 4 5 . >/dev/null
invoke-rc.d cron start || exit $?
fi
which is deprecated if i got it correct:
https://lists.debian.org/debian-devel/2013/05/msg01109.html