Blue Bird Corp

Stockholders and Board of Directors

Blue Bird Corporation

Macon, Georgia

Opinion on the Consolidated Financial Statements

We have audited the accompanying consolidated balance sheets of Blue Bird Corporation (the “Company”) as of September 28, 2024, and September 30, 2023, the related consolidated statements of operations, comprehensive income (loss), stockholders’ (deficit) equity, and cash flows for each of the three years in the period ended September 28, 2024, and the related notes and schedule (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company at September 28, 2024 and September 30, 2023, and the results of its operations and its cash flows for each of the three years in the period ended September 28, 2024, in conformity with accounting principles generally accepted in the United States of America.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (“PCAOB”), the Company's internal control over financial reporting as of September 28, 2024, based on criteria established in Internal Control – Integrated Framework (2013)issued by the Committee of Sponsoring Organizations of the Treadway Commission (“COSO”) and our report dated November 25, 2024 expressed an unqualified opinion thereon.

Basis for Opinion

These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s consolidated financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the consolidated financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of a critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing separate opinions on the critical audit matter or on the accounts or disclosures to which it relates.

Evaluation of Warranty Reserve

As discussed in Note 2 to the consolidated financial statements, the Company's warranty reserve is calculated based on the average expected warranty claims using warranty claims by body type, by month, over the life of the bus, which is then multiplied by remaining months under warranty, by warranty type. The total warranty reserve was $16.2 million as of September 28, 2024.

We identified the evaluation of the methodology, including the assumptions for the average warranty costs per unit and the payment patterns over the term of the warranty, used in the evaluation of the warranty reserve as a critical audit matter.

The principle considerations for our determination were (i) the Company’s methodology and assumptions relating to the average warranty costs per unit and the payment patterns over the term of the warranty involved a higher degree of auditor judgment, and (ii) specialized actuarial skills were needed to assess the Company's process and evaluate the methodology and assumptions regarding the determination of the average expected warranty claims and the effect of those assumptions on the reserve.

The primary procedures we performed to address this critical audit matter included:

•Testing the design, implementation and operating effectiveness of controls over the Company's warranty claim process, and controls over the data, inputs, and methodology and assumptions utilized to estimate the warranty reserve;

•Testing management's process used to develop the warranty reserve, including the mathematical accuracy of the calculation and the relevance, reliability, and appropriateness of the methodology and assumptions and the sources of data from which the assumptions were derived;

•Utilizing actuarial professionals with specialized knowledge and skills to assist in: (i) reviewing the Company’s actuarial methodology in calculating the warranty reserve, (ii) evaluating certain key assumptions related to the average warranty costs per unit and payment patterns over the term of the warranty, in the determination of the average expected warranty claims, and (iii) determining whether the methodology, assumptions, and calculation were consistent with historical evaluations and the aggregate impact of any changes to assumptions.

/s/ BDO USA, P.C.

We have served as the Company's auditor since 2016.

Atlanta, Georgia

November 25, 2024

Stockholders and Board of Directors

Blue Bird Corporation

Macon, Georgia

Opinion on Internal Control over Financial Reporting

We have audited Blue Bird Corporation’s (the “Company’s”) internal control over financial reporting as of September 28, 2024, based on criteria established in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (the “COSO criteria”). In our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of September 28, 2024, based on the COSO criteria.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (“PCAOB”), the consolidated balance sheets of the Company as of September 28, 2024 and September 30, 2023, the related consolidated statements of operations, comprehensive income (loss), stockholders’ (deficit) equity, and cash flows for each of the three years in the period ended September 28, 2024, and the related notes and schedule and our report dated November 25, 2024 expressed an unqualified opinion thereon.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting, included in the accompanying “Item 9A, Management’s Report on Internal Control over Financial Reporting.” Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit of internal control over financial reporting in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audit also included performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/BDO USA, P.C.

Atlanta, Georgia

November 25, 2024