The requirements freeze following the latest release (revision 10) of the Level 1 technical requirements has allowed SADT to stabilise the design of the SKA’s data and timing networks. The Consortium team is now preparing the documentation needed for Critical Design Review, with the Detailed Design Documents for the various sub-elements now at a mean level of 75% completion. Formal end-to-end engineering diagrams of the whole SADT system have been completed. The analysis of the SADT networks reliability has now been delivered and is being used to refine our maintenance and operations plan. The costings of the solutions proposed have matured and the Consortium has made great strides in reducing costs. The bottom line SADT Cost Estimate dropped by €14.9M between June and September 2016; and by an additional €4.0M between September 2016 and March 2017. Final testing regimes are being completed to further de-risk the design solutions and add to the body of evidence submitted as verification of the designs. We are also now in the process of planning for additional, post-CDR testing of the SKA Digital Data Backhaul system using e-MERLIN as a test-bed.