Stellar mass at a given z relative to the final stellar mass at z = 0 for AGN (upper panels) and non-AGN (lower panels) galaxies for galaxies in different stellar mass ranges. The mean formation time of the galaxies, estimated as the look-back time at which galaxies formed 50 per cent of their final stellar mass, τ₅₀ are included for each subsample (dashed lines). AGN and non-AGN central galaxies formed quicker in lower In-V and Out-V regions over W and S, particularly in the low and high stellar mass intervals. AGN central galaxies are assembled systematically later than non-AGN ones.