The special matinee concert, as part of their Beat Again comeback tour set to take place at the Resorts World Arena on November 28, 2020, will now be held on July 3, 2021.
Other Birmingham JLS dates, originally set for November 28 and December 11 to 12, 2020, have now been rescheduled for June 29 and July 2 to 3, 2021.
A statement from the band said: "With regret we’ve had to make the decision to reschedule our JLS Beat Again tour to June 2021 as ensuring the safety of our incredible fans, crew and venue staff is our main priority.
"Our reunion tour is such a monumental moment for us as a band that we want to make sure we are able to give the best show possible.
"Given the amount of time and preparation it takes to produce an event of such scale we’ve had to postpone to a time that permits us to do so.
"We can’t wait to see you all next year and thank you for your patience and endless support. It’s all love."
Those with pre-existing tickets have been told to contact their point of purchase for more information.
The one-off show will be centred around celebrating and honouring the efforts made by the country's NHS frontline staff and primary care workers during the Covid-19 pandemic.
Those eligible for tickets for the show will be all frontline NHS staff working within hospitals across the country including, but not limited to, doctors, nurses, support workers, ambulance staff, porters and cleaners.
Any staff that work within the hospital will be eligible to apply for a ticket. Eligible NHS staff members are entitled to bring one guest with them but will need two tickets.
Tickets are limited to two per eligible person. Eligible frontline staff must bring valid ID with them to the show.
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