Can't install systemback on Elementary os

I'd installed and used Systemback on Elementary OS without any problems a few months ago, but after a format I can't get it installed again:

I followed the instructions and added the ppa and updated, but then I got this

sudo apt-get install systemback
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package systemback

After that, I tried installing it from the sourceforge file (Systemback_Install_Pack_v1.2.0.102.tar.xz) but i got pretty much the same error described in this topic https://answers.launchpad.net/systemback/+question/255102

An now, when I enter sudo apt-get install systemback I get

Reading package lists... Done
Building dependency tree
Reading state information... Done
Package systemback is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
However the following packages replace it:
  systemback-scheduler

E: Package 'systemback' has no installation candidate

Any ideas?
Thanks.