So the little roaster I have uses an app, so you can repeat a profile
Very basic
The green beans have a moisture content, the first phase is drying time, the next phase is the browning or Maillard where you break down sugars etc then the beans get so hot they pop like popcorn this is first crack. Most call the time after first crack the development phase, the time spent here is what gives light medium or dark roast.
These beans first go I gave 70s and were to acidic, this time round 120s and so much better
Each roaster behaves differently so there are no one settings that work only general guide lines
But once happy you can just use the same profile and get similar results