If we assume that OBP-B1 has produced at least one supernova, when did that supernova (or supernovae) go off? This figure presents the PDF of time elapsed since a supernova explosion based on the Bayesian modeling by \citet{Forbes2021}. More recent supernova explosions are heavily favored by the model. For example, there is roughly a 40% chance of a supernova exploding 0-2 Myr ago in OBP-B1, which is 4 times more likely than a supernova exploding 5-7 Myr ago.