All of the accepted abstracts and also the full papers of the accepted ones which have not been selected for publication in Springer would be published in the conference booklet.
The full papers selected for Springer would be only published in CCIS book series.
The papers which have not been selected for Springer, would be selected for the journals (according to the conference website) for consideration.
So, it cannot be said in advance that your paper is going to be published in Springer or in a journal.