This link:
https://headless.earthtime.org/#l=bdrk_detailed,smell_my_city_pgh_reports_top&bt=20210405010000&et=20210406010000&v=40.42532,-79.91643,9.233,latLng&ps=2400&startDwell=0&endDwell=0
shows only plumes, no smell icons:

while if we remove only the plume layer and go to:
https://headless.earthtime.org/#l=bdrk_detailed,smell_my_city_pgh_reports_top&bt=20210405010000&et=20210406010000&v=40.42532,-79.91643,9.233,latLng&ps=2400&startDwell=0&endDwell=0
we see smell reports, but for a completely different time range in 2019:
