The mailing list for listmasters using Sympa

[Simone Dal Maso <address@concealed>]

Hello,
yesterday during a regular apt-get update and upgrade some software were 
updated, and also sympa.
I have sympa 6.1.23.

I was not care about the version, but the surprise was that, after the 
upgrade, I have a new sympa installed, and all my configuration was... lost.
This is not acceptable... sorry but really I think iit is absurde that 
during an update all configurations file were lost.
Anyway, I restored a backup of 2 days ago, and if I type:

apt-get upgrade -s
for simulating, I can see:
 Conf sympa (6.1.23~dfsg-2+deb8u1 Debian:8.7/stable [amd64])



so the version is the same?
6.1.23?
And what can I do now for preventing my system to update sympa and lost 
everything?