• Honeymoon Review indicates material deviation from 2021 Enhanced Feasibility Study assumptions
• Potential pathway forward with wide-spaced wellfield design to optimize resource and assets
• Accelerated work programs to assess economic benefits of wide-spaced wellfield design

Boss Energy Ltd (ASX: BOE) has provided an update on the conclusion of the Honeymoon Review and the initiation of a New Feasibility Study. The Honeymoon Review has indicated an expected material and significant deviation from the assumptions underpinning the Company's 2021 Enhanced Feasibility Study (EFS). This would be expected to impact life of mine production and cost from FY27 onwards, primarily due to less continuity of higher-grade mineralisation, mineralisation not overlapping, less leachability and smaller wellfields. As a result, Boss is formally withdrawing the EFS and confirms that it should no longer be relied upon as a guide to future operational performance. Through the Honeymoon Review, Boss has identified a potential pathway forward based on an alternative wide-space wellfield design that could be suitable to Honeymoon. Boss has initiated a series of accelerated work programs to assess the potential economic benefits of the wide-spaced wellfield design, with an initial update to be provided in Q1CY26, a Scoping Study targeted for Q2CY26, and a New Feasibility Study completion in Q3CY26. The wide-spaced wellfield design could potentially deliver lower costs and improved lixiviant grades compared to the current wellfield design. Boss remains in a strong financial position and will self-fund the key work programs associated with the New Feasibility Study and a potential change to wellfield design.

Boss remains on track to deliver FY26 production of 1.6Mlbs drummed, C1 cost of $40-45/lb (US$27-28) and all in sustaining cost (AISC) of $75-80/lb (US$41-45/lb). FY27 is expected to be similar to FY26 in terms of production and cost but AISC would be ~15% higher than in FY26 given the higher proportion of sustaining capital.

Based on the current wellfield design and prior to the outcomes of the New Feasibility Study, FY27 is expected to be similar to FY26 in terms of production and cost but AISC would be ~15% higher than in FY26 given the higher proportion of sustaining capital. If the wide-spaced wellfield design is successful, it could potentially improve resource recoverability and cost structure at the Gould's Dam and Jason's Deposit satellite deposits.