Comment 7 for bug 1849156

Got bit by this as well, recall fixing it a few years ago but must have clobbered my changes on upgrade bionic -> eoan? Having VirtualBox installed broke it, fix was to comment out this line in /lib/systemdd/system/systemd-timesyncd.service.d and restart systemd:

ConditionFileIsExecutable=!/usr/sbin/VBoxService

Don't recall being asked about a config file change during upgrade although maybe it did and didn't remember. Further info here:

https://askubuntu.com/questions/940311/time-in-ubuntu-16-04-not-updating-from-internet#1005355