Zodiac RIB self-bailer and float switch

[JollyRogerC]

I just acquired a 1999 Zodiac YachtLine 12' RIB. As will be obvious from the remainder of my message- I am not that boat-savvy and the manual has little to nothing to say about the items involved. The boat has two, what I think are self-bailer holes on center in both seating areas. It also has an Atwell Float Switch in front of the engine and an external drain plug in the transom.

I am assuming that the drain plug should be inserted when the boat is in the water and removed to drain when on land. The float switch is apparently designed to kick in if the water level in the small bilge reaches two inches. My questions are these- where does the water from the self-bailers and the float switch exit the boat?

Thanks for any help.