Hi Pete. We haven't been for a few years now. That was in the days when the boat went from Arillas. We would get about 4 hours on Mathraki, which was lovely as over the years we must have explored every bit of it - a most beautiful island. Have been to Ericousa and Orthoni but in my humble opinion neither of them are as beautiful as Mathraki. I think the local ferry goes from San Stefanos but not sure if it's every day and calls at all of the islands. I do stand to be corrected on that. However, do try it. I think you'll find the experience well worth it. After all, time doesn't matter there. There's always avrio!
Ann x