Key assumptions and limitations. We conclude with a number of important considerations. First, this work includes only six oil and gas sites. We do not claim that these results would be perfectly replicated on different sites and under different conditions. However, we believe that this analysis, although limited to six sites, provides an important step towards understanding real world CMS performance. Future work will include an analysis of CMS on a larger sample of sites. Second, the exact degree of near real time quantification alignment is likely a function of the length of the quantification interval used in the inversion. Performing the inversion on longer intervals would likely result in more near real time agreement, and vice versa. However, the amount of data used to infer emission source and rate was not the primary focus of the manuscript, and we believe that using a comparable interval to what CMS solutions are using in practice most genuinely reflects the real world performance of CMS. Third, differences in the near real time and aggregated emission rate estimates between the CMS solutions are partially due to differences in the localization estimates. Section S7 in the SI explores this source of variability by examining near real time and distributional agreement between CMS solutions for 30-minute intervals where the localization estimates from each solution were the same.