Well, Air Berlin isn't just one company.
It is put togehter by several aquired companies of which one is the former LTU. LTU used to be run rather friendly towards its employees and it is still the old LTU crews flying the A330s.
Now Air Berlin is not known to be overly caring of its staff, at least such are the rumors.
Additionally, Air Berlin has hardly ever turned a profit and is now being funded by a company from Abu Dhabi whose name must not be mentioned here. You can check the middle eastern forum to see.
So in my very personal opinion that can in no way be proven, maybe, just maybe, this is a signal by an old LTU crew towards the management.
Maybe...