soee@TachikomaDell:~$ LANGUAGE=C sudo apt-get install -o Debug::pkgProblemResolver=true libkf5akonadicore5
[sudo] password for soee: 
Sorry, try again.
[sudo] password for soee: 
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Starting pkgProblemResolver with broken count: 1
Starting 2 pkgProblemResolver with broken count: 1
Investigating (0) libkf5akonadicore5 [ amd64 ] < 4:15.08.2-0ubuntu2 -> 4:15.12.1-2ubuntu1~ubuntu16.04~ppa42 > ( libs )
Broken libkf5akonadicore5:amd64 Depends on libkf5akonadicore-bin [ amd64 ] < 4:15.12.1+git20160213.2213+16.04-0 > ( libs ) (= 4:15.12.1-2ubuntu1~ubuntu16.04~ppa42)
  Considering libkf5akonadicore-bin:amd64 3 as a solution to libkf5akonadicore5:amd64 10007
Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libkf5akonadicore5 : Depends: libkf5akonadicore-bin (= 4:15.12.1-2ubuntu1~ubuntu16.04~ppa42) but 4:15.12.1+git20160213.2213+16.04-0 is to be installed
                      Recommends: libkf5akonadiwidgets5 (= 4:15.12.1-2ubuntu1~ubuntu16.04~ppa42) but 4:15.08.2-0ubuntu2 is to be installed
E: Unable to correct problems, you have held broken packages.