Both of the prior posts are correct.

I would add that if you are sailing in an area with a big tidal range and a lot of sandbars, you have to do the same thing all the boats in that area do, both powerboats and sailboats:

Coordinate your boating activities with the tides.

Have charts and local knowledge to tell you where the sandbars are (because they move).

Learn to "read" the water so you know when you are coming up on a shallow area and can either change course or pull up your boards and rudders before you get there (so you don't break anything).

Plan your sailing for the day so you won't have to be sailing upwind back to your home destination if it is going to be across very shallow water, because, as Sam said, it is very hard to tack with your boards and rudders up.

Rick and I once sailed our Hobie 18 for 40 miles across the backcountry of Florida Bay from Key Largo to Flamingo. A lot of the way we had to sail around or across mud flats and a lot of the way we were in mere inches of water, with our boards pulled all the way up and our rudders floating out behind.

Luckily, it was a reach for us in both directions. If it had been upwind either way, we would have been in trouble --even if we had had a Hobie 16 -- because the water was so shallow.

My advice is to take water and a picnic lunch in case you get stranded on a sand bar and have to wait for high tide.

You will get familiar with the area real quick, so I don't think it will be a problem. On any kind of beach cat, boards or no, you will be able to go across water depth measured in inches rather than feet.

And if you are in shallow water and still floating and can't tack, heck, you can just get out of the boat and turn it manually to the new direction.