REG — Senior PLC — Holding(s) in Company

For best results when printing this announcement, please click on link below: RNS Number: 5662V Senior PLC 21 September 2026 TR-1: Standard form for notification of major holdings 1. Issuer Details ISIN GB0007958233 Issuer Name SENIOR PLC UK or Non-UK Issuer UK 2. Reason for Notification An acquisition or disposal of voting rights; An acquisition or disposal of financial instruments 3. Details of person subject to the notification obligation Name Millennium International Management LP City of registered office (if applicable) Country of registered office (if applicable) US Name City of registered office Country of registered office Millennium Group Management LLC Delaware USA Millennium Group Management Trust Israel Englander 4. Details of the shareholder Name City of registered office Country of registered office Millennium Partners, L.P. Cayman Islands 5. Date on which the threshold was crossed or reached 17-Sep-2026 6. Date on which Issuer notified 18-Sep-2026 7. Total positions of person(s) subject to the notification obligation. % of voting rights attached to shares.