Has anyone done any testing to see if teams closer to a missions actual level give more bonus missions then high lvl teams blitzing them?

I'm interested because I have my normal team for clearing 12-5 and a speed team for clearing 1-3 / 2-1 and it seems that I get better bonus mission drop rates on the lower level team doing lower level missions then the high lvl team doing those same missions.

I have not done hard testing yet but the trend is becoming quite clear to me. It might just be an RNG streak tho.

I've been using my very same team that smashes the 12-3 map for eons now. Some days i get barely anything, other days i get a bonus mission after every run. Fairly consistent in being inconsistent i'd say, so i vote for a set value.