High level summary of the decision tree used to process all compact “M” sources (i.e. PYBDSF sources fitted with multiple Gaussians) in the PYBDSF catalogue. Following this workflow a decision is made for each source whether to: (i) make the optical/IR identification, or lack thereof, through the LR method (blue and red outcomes respectively) for either the PYBDSF source or one of the Gaussian components; (ii) process the source in LGZ (green outcomes); or (iii) process further in a separate deblending workflow (orange outcomes, see Sect. 5.4). The key parameters are defined in Table 3 and full details of the decisions are given in Sect 6.6, with reference to the branch labels i–x. The numbers reflect the number of PYBDSF sources in each final bin and the percentage is relative to the total number of compact “M” sources in the PYBDSF catalogue.