3.0 S have nothing to do with rng on the part of the trigger...just time + effort = pop...it's just that both values were increased for 3.0 S ranks. Imagine when we thought 2.0 S were open at 24h after maint...it would take 15 hours to pop bonna/croque. I'm assuming SE took this as how we want to pop S ranks, so now in order to pop 3.0 it's not just one and done.