Bats in Soffits and Vents in Brandon, FL
Why the panel end matters
A vented aluminum or vinyl soffit is not fixed along its length. Each panel slots into a J channel at the wall and clips at the fascia, which is what lets it expand and contract in Florida heat. It also means the end of the run is the weak point, and once the fascia has moved a few times the panel lifts and leaves a slot behind it.
That slot opens onto the whole soffit cavity. A colony gets a sheltered space running the length of the eave with nothing in it, no need to reach the attic at all, and a clean drop out into open air. It is a well understood way into a house of this age and construction.
Finding the run that is in use
Not every lifted panel has bats behind it. The ones in use show a dark greasy rub mark at the edge where bodies pass repeatedly, and droppings collect in a line on the wall or the ground directly underneath rather than spread around. On a light colored soffit both signs read from the ground with binoculars.
Getting that right decides the job. The active openings are the ones that receive one way doors, and everything else gets sealed first, so a misread means either a device on a dead gap or a colony sealed inside a building.