TheSkier-
That is something that I hadn't thought about much. If there is a little breeze, we should be in by dusk, but it is something to consider if the air is lighter (of course Lake St. Clair never has little to no air on a summer evening
)
I think that having a flashlight to shine at the sails will be sufficient. This isn't something I would want to mess with in a breeze, but in those cases we will be in before dusk.