My husband and I are planning to stay in Sifnos for a couple of nights in October this year. Our time is not flexible at all .We are meeting family in Athens for most of the time and thought we could slip in an island for a few extra days. My concern is not knowing what the ferries will be doing at a quieter time of year. Can anyone help? What are the chances of us not getting there and back on time? Do the ferries run every day?