Why have they suddenly added a pay rise to their demands, despite only just having one?
Thousands of London Underground station staff are to strike next month in a long-running dispute over pay and conditions.
Rail, Maritime and Transport union (RMT) members will walk out on 4 and 6 October, which the union said would shut down the capital's Tube service.
The union is locked in a row over cuts it said will lead to hundreds of job losses.
Transport for London has been approached by the BBC for comment.
London Underground: Thousands of staff to strike over job cuts
Union members will walk out on 4 and 6 October and shut down the Tube, the RMT's Mick Lynch says.
www.bbc.co.uk