Comment 3 for bug 1667733

Thanks for pointing to the part in the changelog that contains the smb fix Richard. I searched for "samba" not just reading through it :-/

The package instals itself (after placing the raw files) via a postinst script (https://www.debian.org/doc/debian-policy/ch-maintainerscripts.html)
You can find the one that does that for backuppc in: /var/lib/dpkg/info/backuppc.postinst
(this is a cache and might be cleaned)

The install from upstream is conflicting (overriding files) with the distribution one:
Atfer install I see a lot of changes in "dpkg --verify backuppc"
So this breaks your former Distributon based install.

The upstream script asks you for upgrade your lder config which is at /etc/backuppc/config.pl.
If you "just" want to get to the upstream level you have to remove the Distribution one (apt-get remove backuppc) and then run the configure.pl in fresh-install mode.
Afterwards restart the service "service backuppc restart" and the new version is running.

But then this is just the upstream, no updates/upgrades/...
A workaround for now, but I'd recommend picking up the update once it is released and maybe even SRU'ed back.