This document seeks support to allow line setting operations by autoline vessels fishing in Division 58.5.2 to occur at any time of the day/night cycle. The proposal forms part of an adaptive approach to management, which considers the risk status of the fishery, knowledge on the effectiveness of mitigation measures, mitigation performance record of the vessel, seabird mortality levels and assessment of the likely effects of individual mitigation measures to total mitigation response. Since the introduction of longline fishing in 58.5.2 in 2002 seabird by-catch mitigation requirements have exceeded those required by CCAMLR. Evidence from sub Area 48.3 (South Georgia), where both the hooking effort and number and abundance of longline-vulnerable seabird species is far greater than in 58.5.2, suggest that winter fishing with appropriate mitigation presents very low risk to seabirds. This is supported by the results of the first two years longline fishing in 58.5.2: a total of 2.2 million hooks have been set and no seabirds caught during line setting operations. Possible reasons why seabirds have not been caught are the very low abundance of longline-vulnerable seabird species on the fishing grounds between May and September, night setting, the requirement for a minimum line sink rate, the use of paired streamer lines and no offal discharge. In cases where seabird mortality is very low or non-existent it is appropriate to review mitigation requirements, particularly measures that might have adverse effects on fishing operations. Evidence from integrated weight longline experiments conducted in the New Zealand ling fishery in daylight and in summer suggest that the absence of seabird mortality in 58.5.2 is due to the low incidence of longline-vulnerable seabirds in winter, the minimum line sink rate and the use of streamer lines (the contribution to by-catch reduction of a minimum line sink rate and streamer lines, used separately, has not been determined). Removal of the night setting requirement is unlikely to result in an increased risk to seabirds in Division 58.5.2.