Simulated SFHs for comparison with Jekyll. The first row shows a quenched SFH composed of three bursts. The second row shows an SFH where most of the mass was formed very early, and a small burst happened 200 Myr before observation, creating the post-starburst features. The third row shows an SFH with two burst, the last one happening when the galaxy is observed but has a very small SFR . Left: synthetic photometry for the complex SFH (black points) and best-fit model from FAST++ (red line and red squares). Middle: complex SFH (black) and best-fit model (red). Right: constraints on the formation and quenching timescales (t_68% and t_b<1%) given by themodel (orange area), best-fit value (red circle) and true value (black circle).