Avalon Advanced Materials Extends Proxy Voting Deadline Ahead of Special Meeting

Toronto, Ontario--(Newsfile Corp. - October 6, 2025) - Avalon Advanced Materials Inc. (TSX: AVL) (OTCQB: AVLNF) ("Avalon" or the "Company") today announced that it has extended the deadline for shareholders to submit their votes (proxies or voting instruction forms) for the upcoming Special Meeting of Shareholders.

• Previous voting deadline: Friday, October 3, 2025, at 10:00 a.m. ET
• New voting deadline: Monday, October 6, 2025, at 4:00 p.m. ET
• Special Meeting date and time: Tuesday, October 7, 2025, at 10:00 a.m. ET (location as set out in the meeting materials provided using notice and access and posted on the Company's SEDAR+ profile (www.sedarplus.ca) on September 8, 2025 (the "Meeting Materials")

The extension is intended to give all shareholders additional time to review the Meeting Materials and participate in the vote.

Shareholders of record as of the record date set out in the Meeting Materials who have not yet voted are encouraged to do so as soon as possible using the instructions provided in their form of proxy or voting instruction form. Beneficial (non-registered) shareholders should follow the directions of their intermediary (bank, broker or other nominee). Previously submitted votes remain valid; shareholders who have already voted do not need to take any further action unless they wish to change their vote.

If you require assistance voting, please contact Avalon Investor Relations at ir@avalonam.com or 416-364-4938.

About Avalon Advanced Materials Inc.

Avalon Advanced Materials Inc. is a Canadian critical minerals company advancing the supply of materials essential for Canada's future. The Company is focused on developing strategic assets that support secure, domestic supply chains and long-term economic growth. Avalon is focused on vertically integrating the Ontario lithium supply chain through the development of Lake Superior Lithium Inc., Ontario's first midstream lithium hydroxide processing facility, located in Thunder Bay. This facility will serve as a vital link between northern Ontario's lithium resources and the growing EV battery manufacturing base in southern Ontario and North America. Through a joint venture with SCR-Sibelco NV, Avalon is advancing the Separation Rapids Lithium Project near Kenora, Ontario, as well as continuing exploration at its Snowbank lithium and Lilypad lithium-cesium deposits. The Company is also advancing the Nechalacho Rare Earths and Zirconium Project in the Northwest Territories. This deposit contains all light and heavy rare earth elements, as well as yttrium, zirconium, tantalum, and niobium-critical minerals used in advanced technologies across the communications, defense, clean tech, and energy sectors.

Cautionary Statement Regarding Forward-Looking Information

This news release contains "forward-looking information" within the meaning of applicable Canadian securities legislation. Generally, forward-looking information can be identified by the use of forward-looking terminology such as "add" or "additional", "advancing", "anticipates" or "does not anticipate", "appears", "believes", "can be", "conceptual", "confidence", "continue", "convert" or "conversion", "deliver", "demonstrating", "estimates", "encouraging", "expand" or "expanding" or "expansion", "expect" or "expectations", "forecasts", "forward", "goal", "improves", "increase", "intends", "justification", "plans", "potential" or "potentially", "promise", "prospective", "prioritize", "reflects", "robust", "scheduled", "suggesting", "support", "top-tier", "updating", "upside", "will be" or "will consider", "work towards", or variations of such words and phrases or state that certain actions, events or results "may", "could", "would", "might", or "will be taken", "occur", or "be achieved".

Forward-looking information is subject to known and unknown risks, uncertainties and other factors that may cause the actual results, level of activity, performance or achievements of the Company to be materially different from those expressed or implied by such forward-looking information, including those risk factors discussed or referred to in the annual information form of the Company dated November 28, 2024 (the "AIF") under the heading "Description of the Business - Risk Factors". Forward-looking information is based on the reasonable assumptions, estimates, analysis and opinions of management made in light of its experience and perception of trends, current conditions and expected developments, as well as other factors that management believes to be relevant and reasonable in the circumstances at the date that such statements are made, but which may prove to be incorrect. Although the Company believes that the assumptions and expectations reflected in such forward-looking information are reasonable, undue reliance should not be placed on forward-looking information because the Company can give no assurance that such expectations will prove to be correct. Although the Company has attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking information, there may be other factors that cause results not to be as anticipated, estimated or intended. There can be no assurance that such information will prove to be accurate, as actual results and future events could differ materially from those anticipated in such information. Accordingly, readers should not place undue reliance on forward-looking information. The Company does not undertake to update any forward-looking information, except in accordance with applicable securities laws.

To view the source version of this press release, please visit https://www.newsfilecorp.com/release/269212