Well depending on the type of vessel you'll be using Halibut gerenaly will be better in the afternoon if your on a boat. Only because the wind comes up in the afternoon and you'll cover a lot more territory on your drift. In the morning whent it's calm your not really moving your bait/lure over much area. Not to say a fish will bite better in the afternoon or better in the morning.

I can say a second condition that can make a big difference in the bite is current. If you have a good a good current moving things across the bottom not The drift will help you locate the fish. Ussually float tubers can kick along as they fish to cover territory but you don't want to be out there in a tube or paddle powered inflatable when that wind starts kicking up. If your unfamilar with Cabrillo beware it gets windy just about everyday in the afternoon during this time of year. There are days when the wind comes rolling down the hill from PV and It will really blow straight down the break wall. I've heard it houl out at the barge in the afternoon. Not to say a fish will bite better in the afternoon.

JerryG