This paper summarises the historic effort and seabird bycatch mitigation measures that have applied to the Patagonian toothfish longline fishery in CCAMLR statistical division 58.5.2. It suggests that there is now sufficient experience to show that fishing under the current season timing and regime of mitigation measures poses a very low level of risk to seabirds. It proposes that the period during which fishing is allowed be extended on a trial basis to include 1 to 31 October, subject to a three seabird bycatch limit. It also proposes that the 1–30 September period be included as part of the "core" season and the 3 seabird bycatch limit no longer apply in September.