Overview

• Phones on 4G or 5G are set to emit a loud 10‑second siren, vibrate and display a test message at about 3pm on Sunday 7 September, even if devices are on silent.
• O2, EE, Vodafone and Three are texting customers this week to flag the drill and direct them to gov.uk/alerts for information.
• Cabinet Office minister Abena Oppong‑Asare says lessons from the April 2023–April 2024 evaluation and subsequent activations have been applied to improve performance.
• Domestic abuse charities Refuge and Solace warn the alert could reveal hidden devices used by survivors, and the government has published opt‑out steps for iPhone and Android.
• Officials note not all devices will receive the alert, advise drivers to read messages only when safely parked, and stress there is no need to call 999 or 112.