Comment 3 for bug 1840347

http://manpages.ubuntu.com/manpages/bionic/man1/dh_systemd_start.1.html

       -r, --no-stop-on-upgrade, --no-restart-on-upgrade
           Do not stop service on upgrade.

http://manpages.ubuntu.com/manpages/bionic/en/man7/debhelper.7.html

       -Xitem, --exclude=item
           Exclude an item from processing. This option may be used multiple times, to exclude
           more than one thing. The \fIitem\fR is typically part of a filename, and any file
           containing the specified text will be excluded.