Firefighters are expected to form a “guard of honour” to mark the retirement of London Fire Brigade Commissioner Dany Cotton.
Ms Cotton, 50, is stepping down earlier than expected in the wake of criticism over the service’s response to the Grenfell Tower fire.
She had been facing pressure to resign from bereaved families and survivors of the blaze following a critical public inquiry report.
The capital’s first female fire chief had been due to retire in April 2020 after 32 years of service.
Crowds of firefighters are expected to line the street outside the London Fire Brigade’s (LFB) headquarters on Monday to form a guard of honour for her.
A Facebook group called Save the UK Fire Service has called for firefighters from across the country to gather in or out of uniform to send Ms Cotton off with a “show of support”.
It also suggested that crews who could not make it to London could parade outside their own fire stations.
An image it posted earlier this month said: “This is a non-political event, just a gathering of colleagues, families and friends who would like to express their respect for her.
“Her fire family would like to communicate their support to Dany in light of her early retirement.
“Dany remains a pillar of spirit to her colleagues and a competent leader. She will be greatly missed in her position of Fire Commissioner.”
The first report from the Grenfell inquiry found that the LFB’s preparation for a tower block fire such as Grenfell was “gravely inadequate” and its lack of an evacuation plan was a “major omission”.
Inquiry chairman Sir Martin Moore-Bick said more lives could have been saved in the June 2017 fire had the policy of “stay-put” been abandoned sooner.
The LFB said that following consultation with City Hall, it had been agreed that Ms Cotton will bring forward her retirement to the end of this year “to enable a timely handover” to the next commissioner.
Ms Cotton had previously resisted multiple calls for her to resign and welcomed the report’s recommendations, saying they would be “carefully and fully” considered by senior officers.
Commenting on her early retirement, Ms Cotton said she was “proud” and “honoured” to have served London and to have stood “shoulder to shoulder” with fire service staff during her career.
She will be replaced by Andy Roe who takes up the position on January 1 and has served with the LFB since 2002.