The TanDEM-X mission is acquiring a new dataset to provide a temporally independent DEM, called "TanDEM-X Change DEM". This set of acquisitions taken between 2017 and 2020 has a clear temporal separation to the TanDEM-X global DEM data which were acquired between 2010 and 2015. Therefore, this new DEM aims to enable the characterization of terrain changes. Improvements in the acquisition planning and the data processing were necessary to generate this Change DEM with fewer acquisitions but still very high accuracy. For this, the use of an edited TanDEM-X DEM as a "starting point" for the interferometric processing is mandatory.