24 hour advance cancellation policy is in effect for all excursions, penalty is 100%. Starfish Marathon Snorkeling Tours reserves the right to cancel the trip for any reasons associated with weather, lack of customers, maintenance issues and/or repair, or other situations. *Alternate Marathon snorkel sites are utilized when conditions prevent us from reaching Sombrero, and decisions are left in the competent hands of the Captain. No refunds, no exceptions. Check-in AT LEAST 30 minutes prior to departure or your reservation will be forfeited. Check-in cut off times are 8:30 am and 12:30 pm.