X0202 SCHEDULE 13D/A 0001085146-24-001646 0001133639 XXXXXXXX LIVE 1 Class I Common Shares 05/01/2026 false 0001995668 56062L100 NYLI MacKay Muni Income Opportunities Fund

51 MADISON AVENUE NEW YORK NY 10010

Kevin Bopp 201-685-6187 51 MADISON AVE NEW YORK NY 10010 0001133639 N NEW YORK LIFE INVESTMENT MANAGEMENT LLC WC N DE 0.00 0.00 0.00 0.00 0.00 N 0 IA This Amendment No. 1 ("Amendment No. 1") amends and supplements the Schedule 13D (the "Schedule 13D") originally filed with the Securities and Exchange Commission (the "SEC") on March 25, 2024. Each item below amends and supplements the information disclosed under the corresponding Item of the Schedule 13D. Except as specifically provided herein, this Amendment No. 1 does not modify any of the information previously reported in the Schedule 13D. The filing of this Amendment No. 1 represents the final amendment to the Schedule 13D and constitutes an exit filing for the Reporting Person. Class I Common Shares NYLI MacKay Muni Income Opportunities Fund 51 MADISON AVENUE NEW YORK NY 10010 Item 1 of the Schedule 13D is hereby amended and restated as follows: This statement on Schedule 13D relates to Class I common shares ("Class I Shares") of NYLI MacKay Municipal Income Opportunities Fund (the "Issuer" or "Fund"), a Delaware statutory trust registered under the Investment Company Act of 1940, as amended (the "Investment Company Act"), as a non-diversified, closed-end management investment company. The principal executive office of the Fund is located at 51 Madison Ave, New York, NY 10010. New York Life Investment Management LLC (NYLIM) NYLIM's sole member and sole interest holder is New York Life Investment Management Holdings LLC, a Delaware limited liability company whose business address is 51 Madison Ave, New York, NY 10010. New York Life Investment Management Holdings LLC has not, during the last five years, been (i) convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors); or (ii) a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws. The members of the boards of managers and executive officers of NYLIM and New York Life Investment Management Holdings LLC are listed in Exhibit A. 51 Madison Ave, New York, NY 10010 NYLIM is a registered investment adviser and serves as investment adviser to the Issuer. None None NYLIM is organized in the State of Delaware On March 25, 2024, in order to launch the Funds Class I Shares, NYLIM provided a seed investment in the Fund by acquiring 4,992,500 Class I Shares for $10.00 per share (the Seed Investment). The funds used to purchase the shares of Issuers Class I Shares in the above transaction were from existing available operating capital of NYLIM, and none of the consideration for such shares was represented by borrowed funds. Item 4 of the Schedule 13D is hereby amended and restated as follows: The reported securities were initially acquired solely to seed and support the Fund. On May 1, 2026, NYLIM distributed all of its interests in the Fund's Class I Shares, consisting of 5,426,013.221 shares, to its sole member, New York Life Investment Management Holdings LLC, which in turn contributed all such shares to its wholly owned subsidiary, NYLIM Capital LLC. Both the distribution and the contribution were effected at a price of $10.15 per share. The transfers were part of a reorganization to consolidate various seed capital holdings under a single legal entity to facilitate improved tracking and oversight of such seed capital investments. Item 5(a) is hereby amended and restated as follows: As of the date of this filing, the Reporting Person may be deemed the beneficial owner of 0 securities of the Issuer, representing 0% of the Issuer's issued and outstanding Class I Shares. Item 5(b) is hereby amended and restated as follows: As of the date of this filing, the Reporting Person may be deemed to have the power to vote and dispose of 0 Class I Shares. Except as disclosed in this Schedule 13D, the Reporting Person has not effected any transactions in Class I Shares of the Issuer during the past 60 days. Not Applicable Item 5(e) is hereby amended and restated as follows: As a result of the transaction described above, NYLIM ceased to be the beneficial owner of more than five percent of the Class I Shares of the Fund on May 1, 2026. Accordingly, this Amendment No. 1 constitutes the final amendment to the Schedule 13D filed by NYLIM and is an exit filing for NYLIM. Item 6 of the Schedule 13D is hereby amended and restated as follows: New York Life Investment Management Holdings LLC is the sole member and sole interest holder of NYLIM as described in response to Item 2. Item 7 of the Schedule 13D is hereby amended and restated as follows: Exhibit A: NYLIM and New York Life Investment Management Holdings LLC's Members of the Board of Managers and Executive Officers. NEW YORK LIFE INVESTMENT MANAGEMENT LLC /s/ Kirk Lehneis 06/08/2026