On Halibut out of Homer, you're allowed XX per day, I think it's currenlty at 2 per day. Anyway, the way some of the charters run is to go out in the late evening, you catch 1 or 2 before midnight and then after midnight, you catch a couple more. This way they got more hours of charter time per day on their boat and you had a chance at more fish.
For Valdez, it's been a long time since I've fished there, but it was always on friends boats, I don't think I've ever heard of anyone fishing from shore there. I could be wrong.
Bill