WARNING-CHANGES TO BUOYAGE AND CERTAIN FIXED MARKS Navigational aids in this dataset are being amended to the IALA Maritime Buoyage System (Region B) (see NP 735-Edition 3). The relevant amendments will be promulgated by Notice to Mariners or by inclusion in a New Edition but may not be practicable until after changes to many of the aids concerned have taken place. See also L70 in 5011 for symbols used for buoys and beacons in the IALA system.