The spectral efficiency of DOCSIS 3.1 networks is analyzed based on real-world measurements from the nbn network. It is shown how DOCSIS 3.1 can reduce the required number of node split operations as well as postponing them. The article proposes a decision tree to select the appropriate technology enablers such that traffic demand is met with minimum cost. DS and US network migration to DOCSIS 3.1 is described. Finally, long term network evolution scenarios are provided.