DMIRALTY Sailing Directions, South Indian Ocean Pilot, 16th Edition, 2020. Comores, Madagascar, Seychelles Group, La Reunion, Mauritius, Chagos Archipelago and other islands lying westward of Longitude 90 degrees East. Updated to Week 39/20 (24/09/2020). NP39 and e-NP39 South Indian Ocean Pilot (Fifteenth Edition) 2017 is now cancelled. Republished at approximately 3 yearly intervals.