Byron Energy Limited provided the following update on the Company's 100% owned and operated South Marsh Island 58 G3 (G3) and South Marsh Island 58 G5 (G5) drilling program at its South Marsh Island 58 G Platform. As announced on 26 May 2022, the Byron SM58 G5 well had reached a depth of 9,650 feet Measured Depth (MD)/7,672 feet True Vertical Depth (TVD) and logged commercial hydrocarbons (most likely oil based on LWD logs and mudlog shows) in three sands, the I2 Sand, K4 Sand and L2 Sand. Details on this positive result can be found in the 26 May 22 ASX release.

At that depth, the transmission on the top drive unit of the Enterprise Offshore Drilling 264 (EOD 264) jack-up rig failed, and a complete replacement of the top drive was required. Prior to the top drive repair work, 7-inch production casing was run to total depth and a successful cement job was performed. Accordingly, the three hydrocarbon pay sands logged in the G5 to the depth of 9,650 feet MD are now fully protected and the reserves associated with those sands can be booked and ultimately produced through Byron's 100% owned and operated SM58 G platform.

Once the top drive is repaired, Byron will drill the remaining 600 feet to total depth and evaluate the primary N2 Sand target. With the three pay sands logged to date, the G5 is already considered to be a commercial hydrocarbon well and will be completed for production. After completing the casing job, top drive repairs began on Saturday 28 May 2022 (USCDT) and as of Tuesday, 31 May 22, the entire top drive unit had been replaced and testing was in progress.

However, the motor on the replacement top drive was found to be inoperable and a new motor was mobilized to the EOD 264. Work is currently ongoing to swap out the motor and finish the repair. It is currently estimated that this swap will take several days before it can then be commissioned and approved for use.

During the repair time, the EOD 264 has been and will continue to be, on a day rate of zero dollars per day and all unnecessary contract services have been suspended to minimize any expense to Byron. Once the top drive is operational, it will take another two days to pick up the necessary 4-inch drill pipe, test the BOP's per regulations and trip to bottom before operations to drill to the planned final total depth of 10,240 feet MD/8,196 feet TVD and evaluate the primary N2 Sand. If the G5 logs commercial hydrocarbon pay in the N2 Sand, a 5-inch production liner will be run and cemented before completion operations commence.