Aside from using "caution", I would start with a 4-6" semi-transparent weighted eye sand eel patterns (see archives). If the large don't produce, go smaller. There are enough keepers grubbing sand eels with pink lips right now to persist with the big ones, I personally would stick with them through the whole ebb.
Get there early enough to maximize time before dusk. The channel will still be deep and fast, and you'll need to get the fly down to the sand to get their attention. Sometimes the fish are all over the place and none of this applies. As the current slows to slack, but before slack, you should have good fishing if they are in the channel. Look for fish to be in the trenches at slack.
Mike if you are heading down there tonight you'd better get going... don't even try to fish it on the incoming after dusk! Low is ~8:30 and the level is only -.4 (vs. -1.7 this morning, and -1.9 yesterday AM). My advice: don't try for the outer bar unless you have a kayak or something.
I am considering sneaking out there tomorrow AM... much better tide. Some days, evening is better than morning because of the warmth of the flats in the daylight. Once the summer really gets here the opposite is often true (cooler flats water at night).
Wish I lived there so I could experiment opposing am/pm tides over a sequence of days, months, years to draw some kind of conclusion on this.