Mr. Aidan Bishop reports

GPS PREPARES DRILLING PROGRAMS IN Q1/Q2 2026

Great Plains Metals Corp. has provided an update regarding the proposed drill programs at both the Yeoval Goodrich project in New South Wales and the Everton project in Victoria, currently scheduled in first quarter/second quarter 2026.

Highlights:

• Re-evaluation of legacy data has identified drill targets at Goodrich;
• The characteristics of pencil porphyries -- the Goodrich mine, a previously unrecognized pencil porphyry;
• Mount Rose -- a new discovery and an unrecognized pencil porphyry; first-pass aircore drill program planned;
• Everton project update -- a previously unrecognized pencil porphyry with walk-up drill targets.

During December, 2025, Douglas Kirwin and Aidan Bishop conducted a field visit to the Yeoval Goodrich project to inspect numerous gold-copper prospects and to introduce GPS to key landowners. Re-evaluation of legacy technical data has identified drill targets at the historic Goodrich gold-copper mine interpreted to represent the uppermost section of a mineralized pencil porphyry system. Previous mining was centred on a monzonitic cupola with distinctive unidirectional solidification textures based on mineralized samples observed at the mine dumps. A preliminary diamond drill campaign is currently being finalized, and further updates will be provided this month. Discussions also took place with the preferred local drill contractor with a view to implementing the drill program in second quarter 2026.

The characteristics of pencil porphyries

Pencil porphyries are pipelike, vertically extensive intrusive igneous bodies associated with porphyry copper-gold mineralization. While typically smaller in size compared with other types of porphyry deposits, they often contain a higher concentration of valuable metals, making them significant economic targets. They get their name from their narrow, pencil-like shape and often occur in clusters.

Diagnostic unidirectional solidification textures are magmatic quartz bands often observed at the top and inner contacts within a cupola or apex of the intrusion. They mark the transition zone between the magma and the overlying hydrothermal system. The pencil porphyry is the underlying, cylindrical intrusive body, which may extend to vertical intervals of several hundred metres or more. The Goodrich mine is a previously unrecognized pencil porphyry, and the purpose of the drill campaign is to test mineralization below the old mine. During the period from 1868 to 1886, gold-copper mining at Goodrich supported a small local smelter.

Mount Rose -- a new discovery

During the field visit, mineralized USTs were recognized in the dumps of a small historic mine named Mount Rose, located approximately two kilometres south from the Goodrich mine. Rock textures and gold-copper mineralization are identical to those observed at the Goodrich mine, indicating the presence of another unrecognized pencil porphyry. A first-pass aircore drill program comprising 24 shallow holes over a 300-by-200-metre grid is planned at Mount Rose. The objective of this program is to map bedrock geology, alteration and geochemistry with a view to develop drill targets below and surround the old workings. Limited mining at Mount Rose occurred during 1886.

Given the proximity of Mount Rose to Goodrich, a comprehensive investigation of all copper mapped occurrences will be undertaken within a two-kilometre radius of both Mount Rose and the Goodrich mine.

Everton project updates

Meetings were held during December with the lead geologist of the Everton project. The Everton mine is also a previously unrecognized pencil porphyry with several occurrences of mineralized USTs with widespread visible disseminated molybdenite. Land access has been negotiated, and a work program is currently going through approval with a view to drilling beneath the historic mine toward the end of first quarter 2026. Approximately 20,000 tonnes of 1.4 per cent molybdenum was mined at Everton during the period from 1918 to 1926.

The company will provide further updates this month with details regarding the coming Everton drill program.

Aidan Bishop, chief executive officer, commented: "A clear theme is emerging at both the Yeoval Goodrich and Everton projects where the presence of rocks displaying unidirectional solidification textures indicates the tops of unrecognized pencil porphyries. The exciting aspect about these projects is that the pencil porphyries are exposed at the surface. Others may be present nearby under cover. The focus of future drill programs will be to delineate the geometry and size of the system and determine the intensity of mineralization.

"The recognition of Mount Rose as a pencil porphyry cupola was the highlight of the recent field trip. This discovery underscores that pencil porphyries often occur in clusters. GPS is set for an exciting year -- we are certainly amongst the right rocks in one of Australia's most prospective mineral belts, the Lachlan fold belt. I look forward to sharing further detail regarding the upcoming drill programs."

Qualified person

The scientific and technical data contained in this news release have been reviewed and approved by Douglas Kirwin, who serves as the qualified person under the definition of National Instrument 43-101.

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