The following table provides an indicative date for the key milestones in our decision making process. Please note this timetable is subject to change.
| Milestone | Date |
| Public forum | 11 December 2025, 10-11am (AEDT) |
| Submissions on APA's rule 80 application | 19 January 2026 |
| Draft decision on APA's rule 80 application | March-April 2026 |
| Submissions on our draft decision | April-May 2026 |
| Final decision | June-July 2026 |
On 31 October 2025, APA submitted an application for a determination of future capital expenditure in relation to the extension of the South West Pipeline.
We received updated documents from APA on 10 and 14 November 2025.
We also received an addendum from APA on 10 April 2026.
We invited interested stakeholders to make submissions on APA's rule 80 application for expansion of the South West Pipeline by Monday, 19 January 2026.
On Thursday, 11 December 2025 at 10-11am (AEDT) we hosted an online public forum to discuss APA's rule 80 application on expansion of the South West Pipeline.
The combined presentation slides are now available.
On 5 March 2026 we received a letter from APA requesting a pause in our SWP expansion Rule 80 assessment process, pending a potential revision to the application by APA. The AER has agreed to suspend the assessment process until Friday 10 April, to facilitate further work by APA and AEMO on SWP expansion options.
On 10 April 2026, following a short suspension of our assessment process (requested by APA so it could work with AEMO on South West Pipeline investment options), APA submitted an addendum to its Rule 80 application. The addendum reiterates APA’s initial proposal to augment the South West Pipeline by installing 2 new compressor stations, but incorporates early works expenditure for a future project(s) to loop the South West Pipeline, in addition to increased compressor costs.
On 8 April 2026, we received a letter from AEMO, indicating that APA has provided it with additional information on mitigating reliability and operability risks associated with APA’s proposed compression-based augmentation project.
We intend to release our draft determination on APA’s updated application in coming weeks and invite stakeholder submissions. We intend to release our final determination no later than June-July, as per our indicative timetable for this project.