Development of the Greater Plutonio field complex in Angola Block 18 has been supported by 4D since the first monitor survey was acquired in 2009. Existing 4D data over the field had been considered to be of high quality. Here we develop a processing flow including ΔSΔR (the sum of the mis-positioning of the sources and receivers from baseline to monitor survey) thresholding and parallel pairwise binning with transfer operators to further improve the quality of the 4D products, while optimizing the 4D quality for all six possible time steps between the baseline and three monitor surveys.