At antibiotic concentrations close to the MIC, ADEP treatment essentially depletes the cytoplasmic pool of FtsZ20, thereby continuously removing available FtsZ that is needed for FtsZ ring formation and dynamics14. Our data reveal that ADEP treatment leads to the disintegration of early FtsZ rings (framed green) in B. subtilis, while more progressed FtsZ rings (framed red) resist degradation and finish septum formation as well as daughter cell separation, suggesting distinct stages during FtsZ ring initiation and progression. Therefore, our results support a two-step model of FtsZ ring and divisome progression in B. subtilis. In the initial stage, FtsZ ring formation essentially relies on the cytoplasmic FtsZ pool and FtsZ ring dynamics, indicated by the disintegration of early FtsZ rings upon ADEP-dependent depletion of the cytoplasmic FtsZ pool. In the later stage, the more progressed divisome is considerably less sensitive to a depletion of the cytoplasmic FtsZ pool, implying that other triggers take over to drive divisome progression, for example, peptidoglycan synthases that arrive at the divisome during the later stages of cell division.