Deliverable Report D2.1.4 “Third Report on the joint PCP Pilot (Phase 3)” provides an update on the progress of the current PRACE Pre-Commercial Procurement (PCP) on “Whole System Design for Energy Efficient HPC”. This is the last report in this series. The report explains how Phase II of the execution stage of the PCP was carried out and completed. Phase III is then described, including the timing and documentation used. Difficulties encountered during this final stage of the process are presented, with reference to previous European Commission (EC) recommendations. In particular, both the technical and procedural challenges that have been encountered during this part of the project are described. Finally, the lessons learned are presented, in order to take advantage from them for a future use of a PCP.