UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 8-K

Current Report

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

September 29, 2026

Date of Report (Date of earliest event reported)

BEST SPAC I Acquisition Corp.

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: +1 702 287 9776

N/A

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 5.01. Changes in Control of Registrant.

On September 29, 2026, Naoda Investments Limited, pursuant to an instrument of transfer, transferred all of its ordinary shares of BEST SPAC I (Holdings) Corp. (the “Sponsor”), the sponsor of BEST SPAC I Acquisition Corp., a British Virgin Islands business company (the “Company”), to A SPAC (Holdings) Group Corp. (the “Buyer”).

As a result of the transfer, the Buyer holds 100% of the issued and outstanding ordinary shares of the Sponsor, which directly holds 1,375,000 Class B ordinary shares and 277,000 Class A ordinary shares underlying the private placement units of the Company, representing approximately 80.0% of the Company’s issued and outstanding ordinary shares. No changes were made to the directors or officers of the Company.

In connection with the transfer, Yun Chen resigned as the sole director of the Sponsor. Upon such resignation, Claudius Tsang, a director of the Buyer, was appointed as the sole director of the Sponsor and has shared voting and investment discretion with Kam Chi Kin with respect to the securities held of record by the Sponsor.

Item 9.01 Exhibits

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.