You can volunteer at ARK at any time of the year. From April to September/early October, there are direct flights to Kefalonia from the UK as it's the tourist season. June, July and August are when ARK sees most of its visitors and volunteers in line with this. During Autumn/Winter, i.e. late October to March, you would need to take a flight from London to Athens then a local airline, e.g. Aegean Airlines, for the short flight from Athens to Kefalonia. As ARK hardly sees any visitors and volunteers in the Winter months, you will be very welcome if you can come to volunteer during this time!