Water-based paint is different. When water-based paint dries up, you can't wash it off with water. When 303 dries up, it begins slowly washing off with every drop of water. It will take time and plenty of water to eventually remove it, but by the spring it will be gone, unless you live in some very dry area.
Same as Gdetrailer, I don't apply any protectants to RV exterior. 303 I use on my skin-on-frame kayak - on the deck of course, not on the bottom. I see oily residues on water every time the wave splashes on, and by how the water beads up on the fabric I can tell that there is no more repellent by the end of summer.