As has been said, it was likely Starlink birds. There are currently 900+ starlink satellites in orbit, with a planned constelation of 12,000. That 12k could be expanded out to 42k depending on need/availability. Starlink birds are launched in groups of 60 (usually, some times ride shares reduce that number) and are released in a group. They then conga-line their way into their appropriate orbits over the course of a few days to a few weeks depending on what their planned orbit is.
Once SpaceX gets their Starship LV up and running, it should be capable of launching 400 starlink sats in a single shot.
This might be of interest to folks in this thread...
http://celestrak.com/cesium/orbit-vi...ferenceFrame=1
There is a lot of stuff up there.

