Unite members among maintenance, security and Parlour staff are due to walk out from midnight.
The 16-year-old boy punched Mr Jozwik using the “whole force of his body”, the court heard.
Married father-of-four Maris Ozols, 67, suffered a cardiac arrest about 13 miles into the event.
Jessica Urbano Ramirez’s family have spoken of their anger at the loss of their ‘little angel’.
Riot-trained prison staff sent to the Mount Prison, in Hertfordshire, after serious disturbance
The 21-year-old used a mobile phone emblazoned with so-called Islamic State’s black flag.
Former music producer Jonathan King is accused of assaulting nine teenage boys between 1970 and 1988.
Security officers found the “potentially viable” device at Manchester Airport on 30 January.
West Midlands Police say a number of officers have been removed from usual duties.
How did Ciarán Maxwell infiltrate an elite unit of the military and evade detection for so long?