Drivers arrived at work on Wednesday and rightly insisted on proof that the trains had been prepared properly after the absence of fleet staff during the Metronet strike.

At the Central line's Leytonstone depot, a union rep discovered that his train had been prepped by someone who did not have all the correct licences. So he demanded to know how many other trains this person had prepped - and it turned out to be 17! Given it should take around 45 minutes to prep a train, 17 in one night is quite an achievement.

Then another driver booked on and refused to pick up his train. Management had to back down from their initial attempts to remove him from the premises, and word soon got out that the trains had not been prepped by qualified staff and so were not guaranteed safe to drive. By the afternoon, more than two dozen drivers were refusing to drive.

It's a fantastic example of workers standing up to management, and not letting them get away with putting workers and passengers at risk in a bid to reduce the impact of strikes. It is also a great example of workers uniting across grades and companies, as LUL drivers showed respect for the professionalism and standards of their Metronet workmates and refused to let them be undermined.