Item 1.01. Entry into a Material Definitive Agreement. As previously disclosed, on November 9, 2025, Columbus Acquisition Corp, an Cayman Islands exempted company (the “ Company”), entered into a business combination agreement (as it may be amended, supplemented, or otherwise modified from time to time, including by the First Amendment (as described below), the “ BCA”) with WISeSat. Space Holdings Corp., a British Virgin Islands business company (“ Pubco”), WISeSat Merger Sub Corp., a Cayman Islands exempted company and a wholly owned subsidiary of Pubco (“ Merger Sub”), WISeSat. Space Corp., a British Virgin Islands business company (the “ Target”), WISeKey International Holding Ltd., a Swiss company (together with its successors, “ WISeKey”), and pursuant to a Joinder Agreement, dated as of December 12, 2025, SEALSQ Corp, a British Virgin Islands business company and an affiliate of WISeKey (“ SEALSQ”, and together with WISeKey, the “ Sellers”). On August 6, 2026, the Company entered into the First Amendment (this “ First Amendment”) to the BCA with Pubco, Merger Sub, the Target, and Sellers. Capitalized terms used herein but not defined herein have the meanings ascribed thereto in the BCA. Pursuant to the First Amendment, the parties agreed to extend the Outside Date to October 31, 2026. The foregoing summary of the First Amendment does not purport to be complete and is qualified in its entirety by reference to the First Amendment, a copy of which is filed as Exhibit 2.1 and is incorporated by reference herein. Additional Information and Where to Find It

Item 7.01 Regulation FD Disclosure On August 6, 2026, the Company, Pubco and Target entered into a subscription agreement (the “ Subscription Agreement”) with SEALSQ, an affiliate and shareholder of Target (the “ PIPE Investor” and such investment, the “ PIPE Investment”). Pursuant to the Subscription Agreement, the PIPE Investor agreed to subscribe for and purchase, and Pubco agreed to issue and sell to the PIPE Investor, contemporaneously with the closing of the business combination contemplated in the BCA, $10,000,000 (the “ PIPE Investment Amount”) in Pubco Ordinary Shares (as defined in the BCA) (such shares, the “ Subscription Shares”), at a price per share equal to the Redemption Price, as defined below (the “ PIPE Purchase Price”), on the terms and subject to the conditions set forth in the Subscription Agreement. Assuming a Redemption Price of approximately $10.66 per share as of June 30, 2026, the number of Subscription Shares would be 938,086 Pubco Ordinary Shares. The form of the Subscription Agreement will be filed as an exhibit to Target’s Amendment No. 2 to Form F-4 (filed with the Securities Exchange Commission on August 6, 2026). The “ Redemption Price” is the price per share paid to holders of publicly traded Company ordinary shares which have elected to redeem at the Company’s extraordinary meeting of shareholders for approval of the BCA and related matters, in each case in accordance with the Company’s CAC’s amended and restated memorandum and articles of association. Under the Subscription Agreement, Pubco is required to issue additional Subscription Shares to the PIPE Investor (“ Additional Subscription Shares”) in the event that the volume weighted average price (the “ VWAP”) of the Pubco Ordinary Shares for the 10 consecutive trading days ending on the 60th calendar date (or if such date is not a trading date, on the next subsequent trading day) after the closing of the business combination (the “ VWAP Price”) is less than the PIPE Purchase Price, with the number of Additional Subscription Shares equal to the PIPE Investment Amount, divided by VWAP Price (which may not be less than $5.00 per share), less the number of Subscription Shares. Item 9.01Financial Statements and Exhibits.

Item 9.01 Financial Statements and Exhibits. Exhibit No. Description of Exhibits 10.1 First Amendment to the Business Combination Agreement, dated as of August 6, 2026, by and among Columbus Acquisition Corp, WISeSat. Space Holdings Corp., WISeSat Merger Sub Corp., WISeSat. Space Corp., WISeKey International Holding Ltd, and SEALSQ Corp. ────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────── 104 Cover Page Interactive Data File (embedded within the Inline XBRL document) SIGNATURES 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. Columbus Acquisition Corp By: /s/ Fen Zhang Name: Fen Zhang Title: Chief Executive Officer