National mobile phone emergency alert test set to clash with Sunday matinees

An emergency alarm test is set to clash with Sunday matinee performances later this week.

Mobile phones in the UK that are turned on will experience 10 seconds of sound and vibration at 3pm BST on 7 September in order to test a new alerts system. According to the government, the alert system can warn of extreme weather events, such as flash floods, or if there are terror incidents.

It will affect smartphones on the UK’s 4G and 5G networks, even if not connected to mobile data or wi-fi.

The sound and vibration will take place even if phones are muted, though those who have their phones switched off on or airplane mobie will not receive the message.

The alerts can be turned off in advance, which has been flagged by organisations like the National Centre for Domestic Violence, for vulnerable people who have concealed devices at home.

London stage shows with Sunday matinees either starting at, or taking place, during 3pm include Back to the Future the Musical, Come Alive!, Good Night, Oscar, Hadestown, Harry Potter and the Cursed Child, Matilda the Musical, My Neighbour Totoro, Oliver!, Starlight Express, Six the Musical, Stranger Things: The First Shadow, The Great Gatsby, The Lion King, Titanique, Wicked and Witness for the Prosecution.

This follows on from a previous alert in 2023.